When you are acquiring a target down range, meaning you see something with your eye and then you want to find it through your spotter, it is more intuitive with a straight spotter. Having said that angled eye spotters out sell straight spotters like 70 to 30. I think the ergonomics of looking through the angled spotter is just that much more comfortable for most applications. Most tripods don't even go high enough for a full size man to stand up straight and look through at eye level. If your laying prone and glassing, you would have to have your head crooked up at an uncomfortable angle to see through a straight, so just think about the position you will be in and how you will use it, will be mounted on a mini tripod or a full size tripod? You will you be looking up hill, down hill, across the plains? If you are only using it to check hit's for a few moments at a time, I don't know that it will really matter, but for extended glass sessions I think angled unless your always looking downhill.
