Yes I do agree the 3800 V6 in GM cars is worlds better than the 3.8 in the Taurus, T-Bird and Windstar vans. GM 3800's are bulletproof and the cars that have them perform way better than cars with Fords engine.
However isn't most engine problems just from lack of maintenance. Head Gaskets just need replacement when they go bad. Yeah engine went to crap on my T-bird but only after someone put 20,000 on an oil change, oil was as thick as syrup.
Its like tranny issues, draining and putting in fresh ATF and filter every 2 years or 30,000 miles is so worth it.
V8's don't have to be as fuel inefficient as they are, people just need to drive more sensibly. Save the lead foot for having fun, not when commuting to and from work. I mean even 17 MPG on an all highway commute in a 04 Mustang with the 4.6 is quite pitiful. That car should at least be getting low 20's on the highway. At that rate full size trucks are beating that stang as far as MPG goes, Like a 5.3 liter Silverado.
Funny story, when I bought the Grand Prix at the car lot I told the salesman I wanted something fuel efficient, yet still comfortable and fun to drive. He pointed me to 3 different small cars with 4-bangers. I said I did a lot of research and wanted the Grand Prix, the salesman outright laughed at me saying the GP was not fuel efficient. Well guess what, I been consistently getting 24-26 in a mixed driving situation in this car. As of this tankful I have driven 335 miles and still at quarter tank. Mileage that isn't too much different than my friends Cavalier in a similar commute. I'm guessing a lot of the 3800's fuel economy comes from the fact that the RPM's are rather low. Engine doesn't have to work at all to get the car moving. Lightly tapping the gas gets this car moving, not so much the case with 4 bangers.