For pure value: '06 Evo IX MR
For highway drag racing: '05 SRT-4
For ANY type of track racing, including drag: '06 Evo IX
For lowest ET: '06 Evo IX
For highest trap: '05 SRT-4
For user-friendly driveability: '06 WRX STi
For power to price effeciency, including the cost of the car: Civic Hatch

Overall: Evo. =]