I have the Pica Packworks XL or EEP. (The big version). It barely fits my Medium Tallboy. It does not fit fully inflated 29er tires, you'll rip the pockets trying to make it fit. It is however my favorite bike case.
I remove the brake rotors, derailleur hanger and let the air out of the tires (not breaking the bead) and let the air out of the fork, and it fits snug. It does a good job of protecting the bike, and carrying all your gear.
I always carry a small box to hold my pedals, rotors, hangers, tools and extras and it works out pretty well. I also have enough room for shoes, helmet, and all the rest of my riding gear. It all travels well and stays relatively in place.
The only other one that I have experience with is the THULE hard case. I haven't put my FS29er in it, but if I had to guess..it fit with the tires fully inflated. The case is bigger, but in my opinion, it doesn't hold as much gear nor does it keep it very organized. You have to carefully place the items in to fit under the straps and not move around.
DO NOT GO WITH A BAG!!! I regret the first and only time my bike went in a nylon bag...doesn't matter if has a semi-vinyl sides or not, your stuff will get wrecked!!! I did it once and had about $150 in damages...no bueno!