Generally I've found Printique f/k/a AdoramaPix fine for what it is, and toward the less expensive end for the quality they provide. The biggest thing is that they offer different types of prints, and over time have offered other types of prints, and what you get / the quality you can get is substantially impacted by the type of print you order. Not all types of prints are capable of the same quality.
And the second biggest thing is that, as with any printing service, you have to either work on a monitor that's calibrated to an appropriate brightness (maybe say 100 cd/m^2 or so) and profiled (using a hardware-based system) and then tell the service 'no corrections', or you have to trust the service to make final corrections to color etc.
I have had them do some prints for me in the past. Mostly 8x10 and a couple of small canvas prints. I thought they did a good job for a reasonable price. Pretty quick turn around as well.