Green is probably better for daylight but not worth a ****. Visible lasers just don't do well in daylight when limited by federal power constraints. If the target is in a shaded area then that's different. Don't expect much past 10 meters unless you have plenty of time to "find" the dot on your target. Either color is great in low-light / darkness though you still need to be able to see the target.
If you plan on adding a reflex and keeping the scope mounted, I'd consider the Vortex Venom. I feel it's good, it's very small and almost lighter than air. It's 3 MOA and used mostly on handguns. I have it, a tac-light, and a laser on my 10-22 which is used mostly for armadillos and such at night. The Venom is mounted to a Vortex QD mount. The laser is zeroed at 25m and used over 90% of the time. Most shots are 25-40m.