I'm not particularly comparing based on price; I'm leaning towards MoissCo already since I own another piece from them and have always been happy. I don't know much about Wink, but I'm sure their pieces are very lovely as well.
I'm also not throwing customization into the mix, the info I got from Wink didn't include any customization, and the main difference as I mentioned is there may be an under gallery, which I think that additional metal could account alone for the price difference, never mind and other aspects (if any).
Anywhoo, I love both Bella Halos; they are gorgeous rings! I was just curious about the strengths/benefits of each, that's all, given the similar style but different price.