Apexi V-AFC... purpose?

[Sivik]

Hey guys,

I saw a deal on the Apexi V-AFC. I know some people have it and they say wonders about it. I just have a few questions fopr ya before I decide to get it:

1) What does it exactly do?
2) How hard is it to tune for the most out of your engine?
3) How much will it help a stock engine?
4) Will it void out my Honda Warranty if I install it (reason why engine is stock)?

Thanks guys!