Getting most things isn't usually an issue. If for whatever reason we don't have something you're interested in when you're at the store feel free to ask whoever is behind the counter. They should be able to let you know roughly how long it might take for a given thing to come in.
Lately, with GW's rapid release schedule, I've found that nothing really "flies off the shelf." What usually happens is that I overestimate demand and I've got more than I'd like to have for the first couple weeks.
I guess a simple answer to your question is: I don't expect it to sell very fast.
With that in mind, I will not be ordering "a ton" of it.... So I may sell out in the first week. It's very hard to know... Which is why it's super helpful for people that know they're going get something to let me know.