snOwrider, you're right that some guys are using Big Joes for crawling; you're wrong when you say EVERYONE is. They are not bad, but there are a lot of "not bad" tires for serious rock crawling. Are BJ's the best? no...serious crawling requires tall tires, not wide ones necessarily. If you do a search for RC rock crawling, you'll find a number of sites (rccrawler.com, mudcow.com, etc) that are all about serious rc rock crawling; take a look, you'll see a lot of guys using a number of different tires, most without foams, most with the tread patterns heavily modified, many with the tires and wheels narrowed. I see that you use them, and that's great. I have a set too, and they are a decent tire, but they are NOT the tire I use for crawling my TXT. Heck, they're not even in the top three! And yes, my TXT is strictly a crawler, VERY heavily modified for crawling.
What I'm getting at is, there are no absolutes. What works really well with one truck and setup, doesn't work at all with another. Theres a lot more to crawling than just the tires