What other cars have you owned? Do you prefer torque down low (2000-5000) or up high (4000-8000rpm)? If the latter, buy an E46 M3 or any other M car with the S54 in it. If you prefer the lower rpm torque of a turbo'd engine (I do), the 1M is hard to beat.
Another option - test drive a nice 135 and see if you "need" the extra performance and tuning that the 1M gives you. The 135 is supposedly a great car for the money. At 25 you might want to pocket the difference - so that some day you will be able to afford a low mileage 1M