As far as "better", I don't know, but I like the galvanized ones, myself. They seem to keep their shape better, and are more sturdy in my opinion. I have had mine for over 15 years, and they are still intact. I have to replace hog rings, bait springs, and rope every so often, but you will have those issues with any trap. One thing I will mention though, the coated ones won't cut your boat leather quite as easily as the galvies. Unless, of course, the coating chips off the edges of the coated ones, and the metal becomes exposed. Then they will be just as sharp.
But vinyl coated are noticeably heavier.
Cuts are biggest problem with uncoated topless traps. (anything that will cut including skin!) Although time consuming an easy fix is file down all sharp edges... I plan to do that some day, I need a round tuit, lol.