I recently switched to Delta Point Pros on both of my Open Guns. I had nothing but problems with both of them. Going off in the middle of a stage, going dim and not being able to get them to brighten up and having to replace batteries every match. They are both off being repaired right now. I put my RTS2s that I had very little issues with back on both of my guns. The RTSs are staying on and the DPPs are going up for sale as soon as they come back. The point is, I don’t think anything is 100% reliable but I’ve had the best luck with the RTS2s and I like the 8 moa dot better than the 2.5 on the DPPs