as above, Nikasil's on the 328's are the only problem with them.. All were recalled so most i would've thought would have new engines. When finding one make sure you know the car mileage as well as the engine mileage, as a lot of sellers will blag it as a low miler.
Rear top mounts always go on them, and all of the ones i have had tend to eat brakes. I had an R plate M3 evo a couple of years back (Chris Lowe from PF/RSOC owns it now) and only problem i had was the rad went - £550!! :S. Not exactly interested to drive unlike cossies/evo's, but as you said you have the cossie for that. Miles more comfort and loads more goodies than anything else in that pricerange. Try taking a look at the Lexus IS200's / Altezza's and the AMG C class mercs. These all seem to be dropping now...
Chris