I've used r d dots on my hunting rifles for years with success. Nothing too fancy either. Just Walmart crap on a Remington 750 in .308. Longest shot was just over 200 yards on a cow moose. (Heart shot, DRT BTW)
They're nice to have if you're always pushing through the thick stuff, and need to get off a snap shot real quick. I can't thing of another sight that allows faster target acquisition. Works best with both eyes open, as it seems to just print a magical dot on the side of the deer. Someone used to iron sights will struggle to remember to keep both eyes open though. It can still be used with one eye, but you loose the situational awareness of having all your peripheral vision available to you.
Carry spare batteries. It takes a while to get into the habit of turning your sights off after use. If I remember to turn the sight off when not hunting, one cr2032 will last easily through a six day hunt.
Pay attention to reticle size. Mine was 3 moa. Some are 5. Which means if you were to try to shoot a pop can at 100 yards, it would be completely obscured by the dot. Not exactly ideal if you're trying to shoot a tight group, but a-ok for deer and moose.
I recently ditched mine, because I started wading into reloading, and there's no way to compare accuracy when you've got a 3 inch red blob over the bullseye, and no zoom. Now I'm more satisfied at the range, but I hope I'm not disappointed in the bush...