I think the MMGT would be perfect. Can get nice big tires for the taller grasses, bigger engines (can defo handle big blocks), has two speeds, reverse, and the list goes on.
The .18SS from HPI looks good too, but it's smaller, lower to the ground (not good for grass), and can only handle a limited engine and wheels. Same with the CRT .5
Go AE!
I'm not biased BTW...
Since you decided though, good luck with the CRT![8D] Post pics!