Okay so this is how the 2012 Champions seem to be packed.
Stickers - pretty easy to pick out. Just give the side of the pack a slight squeeze - if it gives there is a sticker in there.
In the packs with stickers (24 per box) you will find the showtime holochrome cards and the rookie sensation cards. This means you will get a big hit in 5/24 packs.
In the packs without the stickers (12 per box) you will find the centurion and try machine cards. This means you will get a hit on 5/12 packs.