I had the Romeo with the built in solar charger on a 45-70 encore pistol. I used it hunting for one year and found that it didn't work well in the woods or shadows or with a dark background behind the deer or any time other then the middle of the day. Although it worked great at the range at 100 yards, I couldn't pick out the deer at any significant distance unless the background was high contrast and it was the middle of the day. I switched back to Leupold scopes.
The year I used it, I was trapped in the stand for nearly 2 hours watching an 8pt buck bleed to death with a broken leg 75 yards away through my binoculars. I couldn't make him out through the Romeo sight in the underbrush to finish him off and didn't want to climb down, scare him and send him running.