I voted none despite what people say about sticks and the 4*.

I've had a look around and there really isn't much out there....

Currently I've got a Superstar 60 (flat bottom) which I've just repaired after putting it through a tree. When I next crash it, if its too bad I'll retire it in favour of the Hobbistar 60 I just got (very similar but semi symetrical)

I've also just bought a Brightstar. This is specifically advertised on the box as a low wing trainer and an ideal 2nd plane, it has a flat bottom wing and it looks like it has plenty of dihedral.

The only other plane similar in this respect to this that I know of is the Slow Poke (40 size).