I have used liveaquaria, saltwaterfish.com, and reefs2go. Of the 3, reefs was the least acceptable, issues with DOAs.
Saltwaterfish was next, never had any issues.
Liveaquaria is def king of the mountain. I had a recent order that had 2 coral from the diver's den. The one ended up bleaching quickly, 2 days after arrival even with proper acclimation. They extended warranty a week. The other came on a rock that had some aiptasia on it, this of course isn't really a problem and I solved on my own. This same rock, had blue symphodium on it, ended up having a nudibranch on it that looked exactly like the symphodium. Took me 2 days to realize that it wasn't polyps not opening up. They worked with me to identify the nudibranch and make sure it was reef safe. It wasn't and was removed.