Can anyone comment on the quality of the Sig branded 516/517 metal BUIS?

Are they decent or old Sig Chineseium crap?

Thanks!

I've only fondled them on a SIG 516 at my LGS (not recently), but they definitely seemed to be a quality BUIS. Having played with the Troys (I own a few sets) and the LWRC oem BUIS, I'd rate them right in the middle of those three, with the Troys in top spot.

The kinda blocky-looking ones? They work fine. Had a set on my Gen2 516 and used them for a while, but since my rifle is Cerakoted in FDE I brain-farted and decided appearances mattered more than durability and swapped them for FDE Magpul MBUS sights instead. The same sights also came on my Gen2 MPX; I used them only briefly on the 9mm before switching them out for a set of low profile Bobros, but even there they worked fine and seemed more than durable enough for the job.

Currently have both sets mounted on a couple of AR builds still in the process of completing. They'll probably stay on those builds for a while until I finalize what I want for optics and/or sights.

The ones that came on my 716...Chinese garbage.
The rear one cracked at the base, the replacement Sig sent did the same thing, but not as extreme.
Maybe my rail was out of spec?
Swapped for a set of Troy and never had an issue.
Rifle is long gone now.

The ones that came with my 516 purchased 6 years ago have been rock solid. They are still on my rifle.