KnoxViews carries a user review of the Garmin Nuvi 650 GPS, a fairly high-end unit for driving.

I use the Mio c310x GPS. The Mio went on sale a few months ago for $199, about $150 off the list. So I pounced.

As I researched GPS units before buying, I concluded two things:

First, the main difference between high-cost units and lower-cost units is mainly features other than the mapping and driving usefulness. That is, lower-cost units have basically the same mapping and driving usefulness as high-cost units. The extra money buys other stuff such as enhanced MP3 playing, bluetooth integration with cell phones, more points of interest, picture viewers, mpeg viewers, traffic updating, etc. But the basic maps are the same. More expensive units also often feature text-to-speech (TTS) so that the GPS tells you,”Turn left on Maple Street in 100 yards,” rather than, “Turn left in 100 yards.”

TTS was a feature I wanted, but none of the units within my budget offered it. My Mio doesn’t have it. However, I’ve found I’ve never wished I had it. The directions without it are still so precise that I’ve never gone wrong without TTS. Moreover, the Mio - and I’m sure any other non-TTS units - displays the name of the next street at the top of the screen. Yes, you have to take your eyes off the road to read it, but I place the MIO atop the dash, anyway, so it’s minor.

One review I read of a TTS unit pointed out that the street names are, well, synthesized, so unusual names can get mangled to the point of incomprehensibility. The reviewer said that street names derived from American Indian words especially stumped the TTS, but other unusual names did, too.

Second, brand does matter. The Garmin reviewer says that Garmins are probably the best and I agree, based on my own research. But Garmins are also the priciest - often by quite a lot. It’s seems true that with GPS units, “you get what you pay for.” I was pretty leery of the Mio because it was relatively cheap, but extensive research persuaded me that almost alone among low-cost units it was a good buy. I’ve never been disappointed.

Generally, units made by audio companies (Pioneer, JVC, Sony) didn’t fare well in user reviews. Those companies’ units were heavy on things like picture viewing and MP3 playing, but their mapping and drivability features were lacking, sometimes badly so, according to the reviews I read.

Power management is also something to consider. Most units are rechargeable and come with a in-car power adapter. My Mio has that and a USB adapter that recharges it quicker than the car adapter. Because all the maps are stored internally in the unit, the USB connection just recharges it. It will play MP3s loaded on an SD card, for which there is a port in the unit, but I have never done that. The unit has a headphone jack, which I suppose I could rig to play through my car’s audio system. I don’t see the need, though, since the unit’s own speaker is plenty loud for its spoken directions, even for my artillery ears. Back to power management, the Mio has a setting that reduces screen backlighting by about 90 percent after a few seconds. It returns to full lighting when the unit gives new directions. Very useful for extending battery life. Also, you can use the GPS connected to the in-car charger without exhausting the battery at all.

I recommend doing hearty research before buying, and don’t run out and buy the first thing that looks like a steal - vendors almost always charge a restock fee for returns that can be pretty hefty.

Another tip: the more POIs a unit has, the better. Before you ever use a GPS, POIs available might not seem important, but they are. I have also found that entering custom POIs is very handy.

The 2007 JD Power Co. rankings of Initial Quality Surveys (IQS) is out and it’s good news for domestic manufacturers, especially Ford. The IQS ranks cars and brands on the number of defects identified by customers during the first three months of ownership. The rankings indicate the number of problem per 100 cars.

Ford Motor Company shows dramatic quality improvement in this year’s study, particularly its Land Rover and Lincoln divisions. Land Rover was the most improved nameplate in the 2007 IQS, and Lincoln rose from No. 12 to a No. 3 overall industry ranking behind No. 2 Lexus and Porsche, which is the highest ranked nameplate in the study. Mercury and Ford also performed well in the 2007 IQS.

The overall results are here. Porsche tops the list with 91 defects per 100 cars, earning five stars overall (well, five colored circles), also earned by Lexus, which ranks second. Completing the top five, in order, are Lincoln, Honda and Mercedes-Benz, each with four stars.

Surprises? Jaguar - another Ford company - tied with Toyota for the sixth spot; Mercury nudged out Infiniti for eighth and hyper-expensive Acura comes in 17th, two places behind Chevrolet. Nissan, whose North American headquarters is right here in Franklin, Tenn., came in at 19, dogged by quality problems of new models.

“It’s typical that when you launch a new model, that you will have a few more defects than you may have on the outgoing model,” said Doug Betts, Nissan’s senior vice president for total customer satisfaction. The auto-maker recently introduced the Versa, a new Sentra and a redesigned Altima, which accounts for about a quarter of the company’s U.S. sales.

I remember as a lad hearing the grownups say never to buy a car its first year out, which seems valid advice. Last year Nissan overall had 121 defects per 100 cars; this year, with the new models, it has 132 overall with the Versa an extremely poor 171. But its established models, such as the Maxima, still rank very high.

Another highlight for Ford:

For the first time since 1999, a North American assembly plant receives the Platinum Plant Quality Award for producing vehicles yielding the fewest defects. Ford Motor Company’s Wixom assembly plant in Michigan, which produced the Lincoln Town Car, averages just 35 PP100. Plant awards are based solely on defect counts.

Domestic brands are closing the gap rapidly on foreign labels in productivity and quality. Auto journalist Mark Phelan reports that domestic makers’ production efficiency now only marginally trails that of Japanese marques.

While the Detroit 3 still trail Japan’s Big 3, the gap has narrowed dramatically, said Ron Harbour, president of Harbour Consulting, the Troy firm that rates automakers’ efficiency.

“Toyota still has the lead, but it is a very slim and marginal lead” in the total labor to build a car, engine and transmission, Harbour said.

In vehicle assembly, in fact, GM has closed to within a negligible 6 minutes of labor time per vehicle of Toyota. GM had the most productive plants for vehicle assembly (Oshawa No. 1 in Canada,) engines (Spring Hill, Tenn.) and automatic transmissions (Toledo).

It’s the first time a single company has topped three different categories, Harbour said. Honda’s Marysville, Ohio, stamping plant led the remaining category. …

Efficiency doesn’t guarantee success, but it helps. Labor used to cost Chrysler, GM or Ford $1,500 more to build a vehicle than it did Honda, Nissan or Toyota, but the gap has narrowed to $250 to $300 today.

Eliminating that difference would allow the local automakers to woo customers by adding features without charging more, he said. Think of it as getting curtain air bags, stability control, a killer stereo or a power tailgate free.

Combine that with an appealing and up-to-date car, and you’re onto something. That appears to be what GM has done with the Saturn Aura. It won both Free Press and North American Car of the Year awards.

According to the Harbour Report, it takes nearly two hours less labor to build an Aura than a Toyota Camry. The gap widens to 2 1/2 hours compared to the Honda Accord.

That 2.5 hours difference between an Aura and an Accord comes to a very large sum of money in saved labor costs, I’m guessing a couple of thousand dollars per car, maybe more. There’s much more to pricing a car than that, of course, but like any very large corporation, an auto company’s labor and other personnel costs comprise the largest single chunk of its total spending. Raising production efficiency means that each car has less labor cost in it than before.

But the IQS is not the last word, or even the most important word. After all, any defects a new-car buyer finds within the first htree months will be covered under warranty. Defects in short-term quality measure customer aggravation more than the actual reliability of the cars. What I consider more important is a car’s reliability beyond the three-year mark, when most full-car warranties have expired. For that I found JD Power’s web site of little help. Consumer Reports is the place to go for those rankings (by model only, not by brand). I’ve also found Consumer Guide to be a great resource.