I was about to start a thread when I found this one. I just got back from the Grand Canyon (trip report coming) and really enjoyed my REI 10-30x25 monocular that I bought on impulse several years ago. It weighs 4.5 ounces. I always bring it out once or twice on trips and consider it a luxury well worth the weight. This trip was unusual for me because the landscape is so open and the distant features so varied and interesting. We spent several hours during the hot part of the day sitting in the shade staring at the details of the surrounding cliffs and the birds. I know nothing about birds but love to watch them fly from below and especially from above. I used the monocular a lot this trip but it got tiring after a few minutes even with switching eyes. I really wished that I had brought some light binoculars instead.

I agree that power levels above 10 are almost useless without a brace but I often arrange myself with a some sort of brace when I get in gazing mode, either a convenient rock or even a pair of sticks tied together. Stabilizing one axis is often enough make the higher power levels usable. At the end of this trip I was on the rim trying to find the Clear Creek Trail I'd just hiked and was able to get pretty good detail by bracing the monocular against the guardrail at Mather Point. I really enjoy the zoom because I can acquire and focus with the power set at 10x and hold an image pretty well freestanding, then if I want to zoom in I find a brace and just twist the zoom ring with the image in view. It's much more difficult to find anything from scratch at the higher higher power levels.

I have no idea how good or bad the REI optics quality is but it seems pretty good to me at 10x. Quality definitely degrades at the higher powers but is sufficient to catch details that are missed at the base power level.

I'm going back to Grand Canyon next month on a trip that will involve lower mileage and a more mid-day down time so am seriously thinking about picking up some binoculars. I will be looking at the suggestions above and would welcome any more thoughts.