I found the Great Planes Rapture very easy to build. The only faults I found in the kit were the lack of laser cutting and a few bad plywood sheets. Otherwise, it was a picece of cake to build straight and strong. The performance was great too.

Another excellent option is the 4-Star 40 from Sig. I've built a few of these. The latest kits are laser cut and frame up almost as fast as you can apply CA. The biggest chore was shaping the leading edge and it's no big deal at all. The Four Star is an excellent flyer too.

Everyone elese has mentioned the Somthin Extra. I have this kit but not started it yet so I can't really comment. I do have the ARF version though and all I can say is that this plane is incredible. It will do just about anything... wild aerobatics, relatively gentle landings and it can even be fairly fast with the right engine (in spite of the thick airfoil). Out of all my planes, the SE is probably my favorite for it's all-around performance.