ORIGINAL: ThunderbirdJunkie
XT2=solid, unkillable engine (even if it is underpowered), sorta heavy, but indestructable.
Protos=limited LHS support, engine sucks, don't know anything else about it
No matter what, though, any of the cars you listed are FAST. Especially if this is your first 1/8 buggy. they RIP.
+1 for me. The 24.7 engine that comes with the XT2 is awesome and is actually fast, regardless of what people say. Get the right tune and your doing 40+ easily. If your LHS has parts for the XT2, I would get that. The XT2 has been out for awhile and has sold a lot, and thats for a reason.