Although not ARF, I would recommed the Southern Sailplanes "T-Bird". It's a great 2m glider which you could use very successfully in comps but it's easy to fly and very very tough. It's mixed construction (beautiful FG fuse and foam/balsa wings). This model has been around for some time and is well proven. With different wing options you can have a glider that does it all. I have flown a T-bird (and the Ricochet) and can't say enough about them. The building is a little more challenging than a balsa model but the instructions are well done. The Foam-Rib wing works really well and the fuselage is the best I have seen on the market - ready to use straight from the box. Try these links (the prices are in Aussie dollars so are very good!).

http://www.labyrinth.net.au/~learmon...elections.html
http://www.labyrinth.net.au/~learmont/FRTBird.html

If you are after ailerons, a polyhedral wing will probably not be the best idea - it will tend to counteract the ailerons. By the way, don't use the ailerons on a Hi-start launch, they can yaw the model in the opposite direction. Use rudder to track straight until the release.