I always preorder with EE, and they're always top-notch, service-wise. Unfortunately this year they've not been recieving their cases in the same timeframe as the big box stores, and I've consistently found figures at retail long before my orders with them have been made available for pick-up. I've even attempted to slow my stops to accomodate the idea of getting cases, and they've just not been able to keep up. Unfortunate.
New Force has always been cheaper. I haven't used them, though, since I waited months and months for a wave of figures that never arrived, and ended up finding at retail. Then, unannounced, they arrived. Being locked into the preorder purchase with them and running the risk of that kind of BS happening scared me away.
If trends continue through Christmas with B&M stores getting shipments in the order of weeks ahead of the smaller online guys, I'd place bets on you finding even a small army of 501st before your online order arrived.
But, as always, I've put my order in with EE, and hope they get those cases in a competitive timeframe. They're such nice folks (those that have been there from the beggining, that is
) that I want to make the effort to send business their way. That's a real rarity these days.