I don't have a photo printer so I print everything at Costco. I download the printer profiles for Lustre and Glossy from
Dry Creek Photo. My last steps are: convert to Costco printer profile, convert to 8-bit and flatten image.
For my local Costco, the Dry Creek profiles are for the Noritsu 3111. Just to make sure, on a recent trip, I asked the clerk "When I specify that I'm using the Dry Creek profile, which machine does it print on?" After concurring with his fellow clerk, he points out the machine... a Noritsu 3111. Everything is good right? Wrong.
I go to the kiosk to print some 12x18s (actually, 11x14s that I'm gonna trim down). When I go to checkout, the clerk tells me "Oh, the 3111 only prints 4x6s. the enlargements go to the other machine" The other machine is a Noritsu 2901.
All this time, I've been using a printer profile but Costco has been printing on a different machine

In my opinion, printer profiles are mostly used by semi-pros and pros and they typically print larger than 4x6.
Just thought I'd share.