Forget the radials, they suck. Everyone I know that runs them off road hates them, especially in the mud. I don't know about the new SSR's though. I like the Bias Ply Swampers, but then it's all I've run. I have seen the others in action though, and asked about them. The SX's are mainly for rocks, where a huge sidewall is needed, or if you're running a heavy rig.
The SSR's are available in 35x12.5 and 35x14.5, both a 6 ply, but with 21/32" of tread. The SX's are available in 35x15.5 only, with 8 ply, but with 24/32" of tread. The TSL's are available in 15/35 and Q78 (35x10.5), both with 6 ply, but the 15/35 has 24/32" of tread and the Q78's have 27/32" of tread. A LOT of people in ou club have gone to the Q78's and love them, They used to run 34x9.5" Swampers TSL's and said they can go a LOT more places with these tires. I am still running the 33" TSL's, but only because I bought 4 of them with rims for $200. I plan to run Boggers later, after the 350 upgrade. I do know of a lady in our club who's running Q78's with a YJ 4 cyl, but I haven't seen her in action yet.
These have more info on them.
My recommendation would be to go with the Q78's or the 36x12.5 TSL's. I have seen a guy with the 35x15.5's "float" on a muddy hill and not be able to get anywhere (2" of mud, very greasy). He had Scout II D44's, locked, with an auto and 360. The guy I bought the tires from crept past him with his lifted but open CJ-5 running my tires. The tires were the right width for the weight, something to consider. I like the 12.5" width, although a little narrower might be better. The 8 ply sidewall has also come in handy, I run the tires at 4 psi, but inadventently ran two of them flat last year (NO AIR AT ALL). It wasn't anywhere near the rim and got me out of the woods. It still looked like they were filled 1/2 way with air. The rims had become so dented they wouldn't hold air, in fact, they still don't. It's in the barn now with no air in the tires, I have another set of rims to change to (from 8" to 7"). I hope this helps in your decision making.
'81 CJ-8 Scrambled!
GM151/SM465/NP205 twinstick/7" Lift/33" Swampers/ Scout II D44's F&R 4.10's & Lockrights