i have a zeiss and a leica, both 10-60x straight that i use for spotting bullet holes out to 500m in groundhog matches. I have looked thru angled lens spotters, and it is more difficult and takes longer to find the target thru them. On top of both my straight tubes, there is a small tit, much like a front rifle sight, that you put it on the object you are spotting, look thru the lens and it is always right on the mark. With an angled lens, i am always moving the tripod adjustments back and forth until i find it.