On average, the guy with the angled spotter will be the one asking "where?" The straight spotter will have the target located long before the angled spotter. With brown bears and moose I often sit with multiple glassers looking at distant hillsides for many hours a day and just about every type and quality of glass gets used. Very few angled spotter users are very effective compared to the straight spotter users and a new critter spotted in a new direction/place usually turns into a major cluster for some.
Idahopro and another long-time hunting buddy have shown it can be done (and well), but they are the exception IME.
