If you want a 4x4 buggy to bash take a look at this. I've been told most of the drive line is out of thunder tigers tomahawk nitro cars so it should be plenty durable for bashing around or even brushless power. If you read the info thunder tiger gives about the truggy version of this car it sounds like they had bashers in mind when designing it and durability was something they were also thinking about.
These vehicles are still very new so there isn't a lot of info out yet on them but they do look very promising.
http://www.amainhobbies.com/product_...ucts_id/138554
http://www.amainhobbies.com/product_...ucts_id/138556