I tried a CO-LR, I thought it was terrible bad enough that I sent it back and paid a restocking fee. I got the highest model Armasight sold, got the L3 unfilmed WP tube and even did a hand pick on the tube. The tubes specs were impressive PC 2722, S/N 33.1, Halo 0.7, EBI 1.0, Res 72. Armasight was great to deal with overall I just didn't like the product. Resolution was the issue and not having enough of it to confirm a clear back drop and send live fire downrange on the public BLM & N.F. lands I shoot on. Gaining a clear enough image for target ID was also difficult due a low resolution of the image presented in the scope. I did try the CO-LR with two of my day optics a Kahles 624i and a Leupold VX6 3-18X44 neither was more helpful than the other. I also tried the CO-LR in the daytime with the front cap on as instructed by Armasight to see if it would help, it didn't I've limited experience with with clip-on NV as it's limited to my time with the CO-LR yet I believe that the reason for my issues was the technology not the specific tube, or the CO-LR. Due to my experience with the CO-LR I've adopted the opinion that when you put a day optic behind an NV scope and then zoom in with the day optic your zooming in on the back of the MCP and resolution seems to suffer. It's because of this that I would call the CO-LR a 400-600 yard optic not a 1,000 yard scope as advertised. I do not notice the same issue when I've my PVS14 behind my scope for viewing, resolution is much better however an illuminator is required. I've since given up on a true long range night optic and would not buy another NV clip on without the opportunity to try it proir to buying.