Give me an RD500LC or an RG500 Gamma, and I'd be a VERY happy man.
2 Stroke has a lot of happy memories for me (RD350LC, RG250 Gamma etc etc), but they are a bit crude.
You can't help but love the kick of the powerband, or the smell of fully synthetic 2 stroke oil, or the noise.
However, I love my 4 stroke v-twin, so I couldn't pick between them.