Over the net is simple, and you wont waste time/fuel going back and forth. If you send them online, they are not touched at all. If you go into the store, they should print the photos for you from the CF card with the terminal behind the counter. If one of my associates told you they couldn't do your order, it'd be on.

Still, the best bet if you want the 1 hour 4X6 from the mart, try the online thing, it's very simple. Plus you can send them to any store. For example if you want to send some to family on the opposite coast, just enter that zip and select their closest location. I've seen some 20X30 prints recenty, and was impressed (that is two day service though).