I've been running Win7 for the last few months on a separate drive. The 64-bit version is (and with 4G of RAM in the machine) is at least twice as fast IMHO as the 32-bit version of XP on the same machine.

I had a Buick Regal Diesel with the 5.7L (350 CID). The engine was flawless and came from the dealer with a water separator. They would not sell one without the separator. The downfall of this vehicle was the crappy torque converter. The engine wrenched off 3 torque converters before I had to cut and run from it.