The X1 CRT is outclassed by all the newer stuff
The X2 CRT is a very good choice, and very competitive.
The Hyper ST PRO is also really good, and handles the most like a buggy
The Losi 8-T is also really good but I found it a bit twitchy
Which one you go for really depends on your driving style. If you keep it nice and smooth the Losi is the one to go for. If you like to chuck it around then go for the ST. IMO the X2 is somewhere between the two of them in terms of handling...... to be honset you won't go far wrong with any of them
There are of course other choices (XRAY, Mugen, etc) but I haven't seen enough of them to justify the price tags.