Hi mate. It kinda depends on what your trying to achieve. Do you need a new rear wheel, or is purely for asthetics. And if your going for a new frame are you sure the GU le is the one you want. Dont know the specific geometery, but the GU will be a world away from your onza.(longer,lower, higher BB) Anyway. If your wanting to improve your riding, go for a new frame. If you just want your bike to be pretty, Spend the money on shiney gold bits.