Bill,
Sorry if this comes in after you've made your decision. I put an Ultradot on my Super Redhawk .44 Magnum about 2 years ago, and I love it. Have yet to hunt with it, but after 400-500 rounds, it's still zeroed at 50 yards. It's very accurate at that range, and seems to be so at 100 as well (with a steady rest!), although I don't shoot with it at 100 yards often. I usually leave it switched on while at the range, and it has yet to even appear to be dimming on the original battery (I do carry a spare). If you're worried about it, you could leave it turned off until you see game, because the rotary switch is noiseless (to my ear, anyway).
It took me a while to choose between the 1" and the 30mm tube, but I bought the 1" tube because it really doesn't matter: the dot is just "out there" with two eyes open.
Good luck.