I did a test before and considering I'm pretty rusty after being so used to Swype (I forgot where " and ' were -.-') I pulled around 55wmp so I'm guessing the maximum I'll ever get is around 70, I'll do another test tomorrow.

Never tried programming on the N900, always something I've wanted to try but I'm so often in front of my comptuer or have my laptop on me it hasn't been required.