Gonna have to say mono. The braided line might cause you to loose more fish because there is no stretch in the line. Like on wire, the fish can actually rip the lure out of its mouth because the line has no stretch. If you were loosing alot on the mono, you might not of had enough pressure on him and he just came off. Try tightening down your drags a little bit so there is a better hook set on the initial run before you get the rod. And remember, set the hook.
Jeff