I was just doing a search for Windows 8 posts, and know this is an old post. But, I wanted to share my times to available-in-store. And hopefully compare it to others.
1) 2 days, 10.5 hr
2) 3 hours, 50 minutes
3) 13 hours, 4 minutes
4) 19 hours, 30 minutes
And some of mine have been rejected and the turnaround time for that was as quick as 4 hours.