My advice would be to not move up to a 600, move up to a 400 instead...I wish I hadn't gone up to a 600, took me a long time to get to grips with how to ride it properly, my confidence was knocked when I first got it, which took months to get back, and I dropped it three times If there'd been all the 300-400s around that there is now, I'd have got one of those instead. Accept you will drop the bike at some point so don't go for something too nice/new, it takes a while to get used to the weight and how to park and balancing at slow speed etc. I'm female and short though, it's worse for us