I have the USO and I like it but think a scope mounted level would be better. I just looked at the Horus and it looks sweet! Think they are around 130 ish.
I don't have the cosign on mine. It is a great piece of kit. I bought it after a shoot in MO where I canted the rifle rather far because I was rushing and frustrated (screwed up adjusting my optic early on). It is more a reminder than anything. Sniper 30mm | Flatline Ops?I like how they spelled "assult cache" in there ad. I hope they QC their products better than their ads.
What makes you think scope mounted is better? I've also got the USO level and I'm quite happy with it. It tucks nicely in and out of the way but its still easily visible. I also just recently purchsed the threaded screw for the other side which makes not losing the cover a much simpler task.
I'm now deciding to go with not mounting my scope level with the gun. I find that I actually like to have the rifle canted as it fits my shoulder better. I hold the rifle so that I'm comfortable and then set the scope using a plumb line. Now I find that I rarely need the bubble level as when the rifle feels comfortable the scope reticle is level. I have left the bubble level in place but I now have a remembered position off of center that I look for if I have any question. Sometimes I have to take a shot from a position that will never be comfortable. During these times having a visual confirmation that I'm canted equally to where my reticle is leveled is a nice welcome addition. I do suppose with a scope mounted level I could set it to show level even when its not but I like the stronger more low profile mount that the USO affords me.