Don't remember where I heard about perfectposters.com but I've used them 3 times now and every picture (14-16 so far) has been printed very well. Cost is very reasonable even for the archival pigment prints. Delivery times have been around 4 days after order was placed. The user interface is easy to use for uploading files to be printed.
I just received a print of my big pano from on top of CG. It's 8" tall X 38" long and only cost $10.00. Not bad!
Just thought I'd throw their site out for anyone who might need prints.
Bill