We often hear about it when customer service goes terribly wrong, so I thought I'd share this good experience. Over the weekend I ordered a gallery wrap from Mpix for a friend's wedding gift and it arrived yesterday, much faster than I expected. The print looks amazing, but I noticed that they put the hanger in the wrong place. The photo is a horizontal orientation but the hanger is set for vertical, so I emailed customer service tonight to see if they'd correct it. Since I emailed at 8pm and they're east coast-based, I didn't expect an answer tonight, but I had a reply within 10 minutes. They apologized for the mistake and offered to send me the hardware to fix it myself or to have me ship it back so they could fix it. I opted to have them do it (since it's a gift, I don't want to ruin it), and within 20 minutes of my first email, I had a shipping label in hand. I've ordered from them twice before and both orders were great, so I was really happy that they were able to turn a mistake into a good experience.
I love Mpix! I used them for developing my relative's photoshoot and their quality and service was beyond exceptional. Glad to hear that you had a good experience with them!