Computer

As Wes said, for most folks it doesnt make sense (unless it's something screwey like you're getting the kit for free).

If you want to search, try "PIH conversion" or "A9L Conversion."
Good luck.
 
If you can find a 1st-gen PIH kit from PRO-M its plug n play. A 2nd-gen PIH kit requires minor rewiring and a few other items to work. Both are discontinued so hunt classifieds and Ebay for one.
 
I think that he meant that the A9L is a slower, less capable processor than ours. Said another way, our processors themselves are better but the factory tune that's loaded into them sucks.

This whole debate is not unlike EFI vs carb (but it's EFI vs less-finicky EFI). People always joke about going carb when a Fox III or IV is too hard to get running decently. Going carbed might be perceived as more user-friendly but it most certainly is a step backwards in terms of performance under every condition and overall streetability. I see the A9L vs T4Moo debate as kind of the same - the A9L has a more forgiving tune (like a carb) but that doesnt mean it's better.