Only the drivetrain is different between the '05 and '06 cars. The '07 is the face lifted 211. It has a slight advantage in that it has lost the SBC brakes and 2nd battery.

Frankly I'd go for the '05 because the m112 and 722.6 are very reliable and durable. I personally passed on buying an m272 car from that era because of the risk of a repair in the four-five grand range.