Adrain :

This is kind of tough to advise on, because some bi-planes do fly as good as trainers, but the trainer is still going to be more forgiving, there designed that way.
My first plane was a bi-plane, and I crashed it, but it was because I got disoriented. I think I would have crashed no matter what it was.
It was a Midwest Das Bipe Stick, if any of you remember that one, It really flew good, but the trainer I got afterward was easier to handle.
Ive had several bipes sense, I got a Sopwith Pup that floats around slower than a trainer can, but its the fact that if something was to happen, You would be losing allot more. Most of your bipes are going to be somewhat scale or a nice plane at least, and you would be worried about it, as compared to a trainer, most of them are simple and not that interesting or big of a risk money wise, you can relax and learn easier.
If you were to get one to build, the Sig Hog Bipe or BUSA Phaeton II are good choices.
After crashing my first bipe, and then going to the trainer for a while, I then got the Phaeton II and then really started enjoying flying, I still remember those days, Thats the funnest time of the hobby, when touching the wheels of that bi-plane on the ground over and over.

SEEYA, TIM