The BFG tire all terrrains T/A tires are KO, mud terrain T/A are KM, and Krawler T/A are KX, but Baja T/A do not have a letter. The letter is after the name on the sidewall.
http://www.bfgoodrichtires.com/bfgap...og/index_7.jsp
The pro-comp tires do offer a lot better grip in all conditions than the BFG's. They also have an 18" now so I can add them to my Titan to replace the stock tires.
http://www.procomptires.com/xterrain2.html