My wife and I test drove a Honda Civic Hybrid. My colleague also owns one and I've driven it from Nashville to Chattanooga. The Civic Hybrid is much nicer than the standard Civic. It's VERY, VERY quiet and all the extra weight in the back makes it ride smoother.
However... For the same $$$ we were able to buy a much roomier Jetta TDi Wagon that uses 100+ year-old diesel technology. We also got leather seats, sunroof, CD, etc., etc. And the car feels like a European import, not a Rice-burner.
This is basically my first new car. I'm used to 25-year-old VW buses, 200K mile Hondas and Toyotas, and even a 180K mile Porsche 911. I plan to drive this car for at least 10 years. That means I plan to drive it well into the years that I have to crack the hood and get my hands dirty. When I looked at the technology of the hybrid: two motors, complex charging system, transmission that magically manages the motors and provides breaking feedback into the charging system, etc., etc. I said "No way!"
Granted, the new "Pumpe-Duese" TDi is a bit of an engineering marvel. The injectors get the fuel up around 30K psi. And being a Direct-Injection and not CRD, the injectors are pricey (about $800 for a set of four). But that's still far less than the price of a new battery-pack for a hybrid.
The diesel is louder than the hybrid. Much louder. In fact, it's louder than a normal gasoline engine. But it's quieter than diesels were 10 years ago and accellerates like a normal car. It also cruises at 90mph with ease.
As far as cruising speeds, we were a little heavy-footed. Driving in the West - long distances and slow-changing scenery - makes you want to just get to where you're going even faster. So we were averaging between 80 and 90. Between Las Vegas and LA, traffic was cruising around 100. I was glad I wasn't in a VW Bus!
I logged my mileage and fuel purchases. I still need to calculate the final usage. Because of our speed, I doubt we got the EPA 42mpg. It was probably closer to 38mpg.
We had absolutely no problems and drove about 12,000 miles.