I'm a librarian who loves anime, manga, and reading a wide variety of genres.
I'm going to try be better, from here on out, about listing the name of the translator when I write reviews about translated works. Including manga, I think, although I tend to notice problems in novels more than I do in manga.
Out of curiosity, I just went through my entire Japanese novel collection (20 different series or standalone works). I had expected to see many of the same names listed over and over, but that wasn't the case. Almost every single volume (not counting multiple volumes within a single series) had a different translator. One book didn't even list a name, just a company: Translation By Design.
The only names that popped up multiple times were Alexander O. Smith and Elye J. Alexander. They worked together on The Twelve Kingdoms, published by Tokyopop, and The Guin Saga, published by Vertical. I haven't read any of The Guin Saga yet, and it's been four years since I last read any of The Twelve Kingdoms. I remember The Twelve Kingdoms being a little clunky, but better than some translations I've seen (Oh, Blood+...).