Bought my first set of lens on vxtuning origianlly. Installed easy enough and looked good on the car. Ended up looking fine and clear until I got a stone chip. Coupled that with a bad projector retrofit (tried to reinvent the wheel mounting the projector, and got into too much modification), I just swapped them with a new set of retrofit lights recently.
This second set I think I purchased a cheap China pair on eBay. They too seem fine so far. Install did not come with the black sealer tape, so I ordered a roll of that buytl rope sealer separately. Seemed like everthing lined up, but noticed one issue on the cheap lens. One of the clips won't stay latched. Seems like there's an under-molded feature, so the latch doesn't have enough meat to grip to. 3 of 4 ain't bad though.
I'm sure some small wave imperfections we're noticed in any lens I've seen so far, but nothing hurt the fit or light projection. And at the end of the day.... SOOooo much better then plastic lens!
Conclusion, check of the vxtuning kit that comes with the sealer (don't have to mess around looking for a place to purchase). Or any should be fine.