The only cars that would be an upgrade to the one you have are the Mugen mbx5, the TTR (which you said you don't want), the Kyosho 777sp2, and the XRay...personally, I'll be looking at an Xray soon. You wouldn't enjoy the swift I don't think, if you are used to an X1. By the way, I have heard (and after some research, I believe it) that the RD Logics Sho is a great buggy. Even if it does have a stoopid name. It's very cheap and a good racer, so they say. If you wanted to take a chance on something cheap, that might be a good bet...