I don't plan on getting a new car for a while, but I always like thinking about things that I don't have. Both are around the same price when specced out the way I want them. The main difference is this: The 328i is more elegant, possibly more reliable, but will be more expensive for parts outside of the 4 year warranty/service program. It's also a poised car built from exceptional materials in Germany, and the Germans aren't known for sloppiness. If I were to get one though, I'd go for the luxury line simply because I'd never take it to the track. I sat in one, but never drove it. I loved the interior, even if it was a bit small. On top of being fast and nimble, it's very efficient. The iDrive system is a thing of art, and I love all of the different settings you can use. The SRT-8 is a brute, but seems pretty refined from what I've heard. I've never been in one or driven one, but it's hard to argue against 470 horses. And the sound... That said, I'd never take it to the track, probably. It's not efficient at all, but it has such a great personality. So, if you had 47k to blow, which would it be, and why? Or would it be another car alltogether?