Just a couple examples..
Aimpoint Comp M = 150-250 hours
C-More = 300-1,500 hours
These are only two off the top of my head. Each company/model lists the battery life in their specs. The wide variance in hours is because of the ability to adjust dot brightness. Choosing a higher dot brightness requires more power.
There was an add that ran in Shotgun News for NIB factory Colt 4Xs, both in standad and illuminated. It may still be in the newer ones, I don't have one around to check.
This is just a poor memory recall, but I think the standard 4X Colt sold for $249, and the illuminated reticle 4X was $100 more.
All it takes is a trip to the
OPTICS board at
www.ar15.com(Use 'Colt' in the search engine.) If you go back 9-month(max), you should find several reviews. You could also enter 'battery life' into the search field, and find out what people are gitting during normal operation of different red dots.
As a side note:
I bought one of the new Grand Slam Weavers for my carry-handle A2 ARs. It is the fixed 4.75X(I know, strange number), with a 40mm objective. These are the least expensive
one-piece tubes I've ever found. Very rugged. It also has great clairity. I think Chris at
www.riflescopes.com quoted me $229, but I had my dealer order me one for $299, because I'm such a great 'business man'.(Got screwed
). I will be buying another for my whitetail rig.
My flat-top scope is a 6X42 Swarovski. I had this before I bought the Weaver. Everyone needs at least one Swaro in their collection. That's what I was told anyway. If I could do it all over, I'd have bought 2 of the Grand Slams instead of the European model. Both are great in the dark.
I hope any of this helped.
Good Luck