I started out on Ninja 500 last year, got bored quickly, then moved up to a Ninja ZX-6R. I plan on getting a 1000cc bike once I get back from Afghan next year. I do feel the 500 was a great beginner bike to start out on, and if you are a person that likes to push your limits a little, then I'm sure you'll want to move up soon as well, (especially when you see other peoples bikes). Whatever you choose to get, just make sure you respect what it can do.