I use titebond II [for it's watertight abilities] for the initial basic structures and basic sheeting (for problem sheeting I use thin or medium CA for that stubborn-to-sheet wing), and when I need it to hold better while it is drying I add a drop of thin CA while it is setting. For the firewall, landing gear blocks and braces, wing center and dihedral braces, as well as attaching the stabilizer and fin to the fuselage and all other high-stress areas I use 5-minute epoxy for the no-need-to-wait quick gluing jobs and (most-of-the-time) 30-minute epoxy. To fuel-proof the engine and fueltank compartment, as well as attaching the fiberglass cloth to the wing center, I use 30-minute epoxy thinned to a syrupy texture with isopropyl rubbing alcohol (just a few drops is usually enough)

P.S: I used to use CA glues for all the basic structure with epoxies in all the high-stress areas. Until the glue stuck to my hands and everything else around the work bench. And the vapors from the CA - wow what a rush [:@][sm=bananahead.gif], not to mention the stinging eyes .