Oi! 12 seconds! My ancient JVC 5 disk changer changes very quickly. It's a little noisy now, but I really don't notice much of a difference between the time to play from one disk to the next (on random) and one track to the next (on random). I'd say go for one of the big changers, but I don't know the speeds or noise on them.

I am the Doctor, and THIS... is my SPOON!