I have a 55mm black Tengyun v1, and a 56mm stickerless XS. I love the feeling of the Tengyun, and the performance is outstanding. However, the stickers are chipping (that's my bad), and now it's harder to lookahead/track pieces since there is less to look at, on top of the smaller size of the pieces.
On the other hand, the XS is 1mm larger, and stickerless, meaning I can easily find pieces when I'm solving. I haven't really found the perfect setting, but the performance is pretty good despite the not-the-best-feeling-compared-to-the-Tengyun. The XS is simply more practical in my case, and for this reason I found myself using it more than the Tengyun.