There's been a couple of threads about this in the past:
Here's one I found:
http://www.rc-monster.com/forum/showthread.php?t=13183
Like Finnster I've tried a myriad of motor/battery/wheel/tire combos in my CRT.5 and the only conclusions I've come to for my setups are:
-It takes about 925-950W peak to really push this buggy around when geared in the ~40-45 range.
-When using 1/10 buggy tires w/16T pinion or 1/10 truck tires with 13T pinion the speed is about the same and so is the power output.
-I keep going back and forth between the buggy and truck tires because there are different aspects of running with each that are both positive and negative, but I think the 2.8 Anacondas are the best on-road tire pick for parking lot running.
I'm currently running with a 5S 2600 TP pack and 1512 2.5d (2050kv) on a MM and I love the setup. More than enough power and great temps. I like the additional weight to help stabilize a bit more from bouncing around all over the place.
The one problem I have with the CRT.5 more so than any other car I've had is that on any sort of grass surface it is extremely prone to flipping when you turn - even at very slow speeds.
I have not had an LS10, but I have to say I am very tempted to get one because of the flipping problem and also that the front upper arm turnbuckles have a real issue with snapping.