Why not go with a World Models Sky Raider Mach I?

http://www.airborne-models.com/html/...p?ProductID=15

At $69.99, it boasts the same kind of semi-symmetrical airfoil as the Hangar 9 Arrow, but at half the price. You could pair this trainer with Super Tigre's excellent GS-40 ringed ball-bearing 2-stroke engine for only $49.99 and get both the engine and airframe for the cost of the Arrow alone. This might be the best value on the market for a high quality trainer airframe and engine.

The two options you're currently considering are both terrific as well. I just built and maidened a new Tower Trainer .40 MkII ARF to replace my old Hangar 9 Easy Fly 40. The Easy Fly 40 was still flying great, but I bought it used and there wasn't a straight line left anywhere on the plane. Crooked tail, cockeyed wing, bent landing gear... I just thought a nicer looking trainer might be nice.

I had a few minor build issues with my Tower Trainer ARF, so I'm more inclined to recommend a Hangar 9 or World Models ARF now. There were a couple of spots on the Tower ARF that required some minor Dremel surgery to get servos fitted properly, and the plane came out very nose heavy with an O.S. Max .46 FX on the nose. I just shimmed out the upthrust from the engine mount though, and it's flying very nicely.

You hit the nail on the head when you said, "Too many trainers to choose from." Good luck and good shopping!