I am partial to RCCA open 'b' rules, so I prefer the .25/.30 size ships. It really depends on what the other people you are flying with are using. If you use a state of the art 'b' ship, and fly against gremlins and spads, you will probably destroy the gremlins and spads, which could cause your competition to dry up. The typical 'b' combat ship has a foam wing made with 40 psi foam, reinforced with 1/8 fiberglass rods top bottom and front, then covered with ripstop nylon. wingspan is usually at least 64", and may be over 72". (a big wing is like adding bigger guns). fuselages vary a lot, some with gutter pipe, aluminum channel or angle, HDPE (cutting board material), circuit board material. Tail feathers are almost all made from 4mm coroplast. check out http://www.rccombat.com for more info than you ever wanted on RC Combat. Some of the guys at SMRCC flew combat a few years ago. They flew .15 size profile models. I think it has been a while since anyone over there has flown combat. There is also a great group out at longview lake, and some interest in KCRC. In smithville, we have 5 members who fly combat, me and one other guy are interested in national competition.