I've been looking at the TFI and the pc and I like the price of the tfi and the fact that you don't have to download maps, but can the tfi increase the rev limit on my 07 sportster like with the pc?
No, the TFI can only alter fuel. You would need an HD download to raise the limiter if you run the TFI. I left the stock limit on my RK because the cranks in the 96 engines aren't as good as they could be and it's only inviting a disaster to twist them too high. Besides with stock cams and heads, the engine has nothing to use above the stock limit, it runs out of steam long before.