With the BME 50 you should be looking at an all up weight no greater than 23 lbs. for serious 3D. I would also be looking for a plane with the size between 28-31%. If a 33% falls in this weight range then go for it but be careful sometimes the weights can be deceiving (example if it says from 22-25lbs I wouldnt go with it) YOu are looking for something around the 17lb mark for all out 3D.

I would advise against the DP models to learn 3D on. They do 3D good but their not the easiest. I would suggest some of the aeroworks models, some of the new extreme flight r/c models, the columbo anderson models, the Kangke Laser, a 30% Carden or something of that nature.

Really it doesnt matter which model you pick. The extra 330 is popular now and so is the Edge 540. Any of the high performance aerobatic line will do just fine. I would kinda stay away from the bipes for learning. They are temperamental to set up for a harrier without dropping a wing.