I am wanting to get one as well - but I found that I'm too short for most bikes. I talked to a guy at a Suzuki place and he told me that I should get a GSXR 600 (since that is what I want) and put a lowering kit on there so I can ride it ok.

A friend of mine had a Ninja - and had nothing but problems with it. An ex of mine had a Honda F4i and that thing was great. it was in 2 wrecks and is still running (of course, there was some body damage) but they hold up well.