The software program obviously favors any AI aircraft as they appears never to stall too easily.
I've seen plenty of AI stall and crash, so my definite impression is that the AI uses the same flight model.
What are some tips for stall problems?
Tweak until you can get stable 50-60 fps. Any lower and there is such a lag between control inputs and aircraft response that you don't get the right feedback, and aircraft control becomes a messy nightmare.
Keep in mind that WOFF is based on the old CFS3 engine, and it's possible to squeeze excellent performance from a modern PC, provided you find the right graphics options for your machine; it takes lots of fiddling, testing, rinse and repeat, but it's worth it. You'll be surprised how different the flight models feel once you hit the right spot, fps-wise.