Could not assess accuracy of sights because they wouldn't fit. The polymer for the area that's supposed to slide onto the rail is very poorly molded. I could get the rear sight on, but the front sight was warped just enough that it would not slide onto the rail. When I finally managed to get the front sight to fit, it was so tight that my gun's metal rail has begun to chip away at the plastic. Tested what I could with my rear sight. The flip-up function was nice and snappy and works exactly as it should, however I was quite disappointed with the quality. If you need a cheap pair of irons and don't mind chancing it to see if you can get a pair of these that's molded well, I'm sure these will get the job done. Unfortunately in my case, these were unusable out-of-the-box and I would personally not recommend them. If Magpul MBUS Flip-Ups are what you're looking for, you're better off getting the ones from PTS or the real thing.