I've got a Tamrac Super Pro 14 shoulder bag and a Tamrac Expedition 9x rucksack. I can get 2 gripped bodies, one with a Sigma 150-500 OS and one with a Sigma 24-70 USM attached, 7 other lenses including a Canon 70-200 f2.8L IS MkII, a couple of flash guns and straps, cards etc.
I think either one of my bags would be overkill for a 5D2 and 50-500 but they do lots of different sizes in the same models. The bags are extremely well made and are huge but they are comfortable to carry.