I think I have had 7 or 8 of them in total. Never had an issue and would buy again. You do know that A LOT of shooters, hunters, military and police uses them, right? They are more than proven.
I have seen the spuhr mounts but had never seen the rings by themselves...
str-4 I was wondering the same myself. .
I like the fact that the spuhr mounts and rings both include a bubble level in their product thus not having to add another object onto the rifle.
I've seen some folks actually prefer not to have a leveling device on their rifle but I am pretty sure I am not even close to their skill set