I use an Epson Stylus pro 9800 for most of my printing. Definitely not a home printer; it isn't cheap and prints on rolls up to 44-inches wide. Just one of its eight ink cartridges costs nearly $100. But to my eyes, the output is exceptional. I hope to eventually get a printer for home that will give me the same results on a smaller sheet. I currently have an Epson 1280 at home; good, but not a match for the 9800. Also, the 9800 uses Epson's Ultrachrome K3 pigment-based ink, so the prints will last a very long time if they're stored or displayed properly. The 1280 is dye-based, so it isn't as archival.
I want to try Mpix, as I've heard good things -- and I especially want to try the metallic paper. But having had complete control over my prints for so long, it is difficult to give it up.
SSB