Hi there. There's loads of us that used to have CTR's. I loved mine and if I ever needed four seats again I would have another. The zed is in a different league though and i'm sure you'll feel the same. My son now has a CTR and I used it the other day and it was still great fun, I'd forgotton how quick it was but no comparison to my zed.
As said above, don't rush into getting the first one you see and if you can get one from a forum member you know you'll have a good one! Good luck.