Fastest Completion?

You don't have to be a speed runner to be fast, but what is the fastest you've ever completed a Pokemon game (defeating the Champion)? Have you ever purposefully tried to complete the game quickly or do you wander around the region grinding in order to ensure victory?

Personally, my fastest ever completion was on FireRed and it was something around 10-12 hours. I literally did no grinding and just assembled a team that countered the Elite Four perfectly, also, I'd gotten to be really fast at the game ever since I bought a fake copy of LeafGreen on holiday that could not save, thus I would try to get as far as possible in one sitting xD

I've taken as low as 10 hours as well, I think. I mostly played with the cheaty buff starter/revive/fodder team, though, so it may not qualify ;p
Recently, I've been playing with more finesse, so I take longer, but cheat less :p I think I'll be trying a speed run soon, though, so we'll see if I can do better.

that probably is my pokemon Alpha Sapphire at 15:50 and my slowest is Sapphire at 99:00

Hands down, my Alpha Sapphire game was the quickest game I've ever completed, beat it at around 8 hours x.x
But I'd also completed my X game pretty fast too, around 10 hours :3

I beat Sapphire with something around 5 hours 50 minutes. Don't know if Ruby would technically be faster or not, but I would guess not, since "MAGMA" is longer than "AQUA" (and appears more in the game).

XY for me I think. I beat X two days after getting the game.

Black came second for me with three days.