Buying a red or green dot depends on what you see better ! Amber /gold is a dot optic color red/green color blind folks can see but there again it is up to you to find the one YOU see best . I started with a ultra dot , red 2moa optic back in '90 on a revolver I hunted with and around 2005 a m&p early core pistol I added a RM02 to it but as green was not around yet to try . When I had to chance to check out a holosun green circle dot for a handgun I also notices how much brighter - clearer my field of view was do to the coating on the lens holosun used compared to triijcons RM optic so I made to switch to holosn green soon after they became available to the public .
Now today there are a other green dot optic options , even circle dot so its your problem to find what you like best . You can also add a magnifier to a carbine but that adds weight too so time ti decide the type of optic and power level you may want or need . For a carbine I'm not all that sold on a dot optic . I am a aim small shoot small sort of guy going back to '73 hunting in sw fl hardwoods swamps and dots optics limit accuracy as yardage increases along with picking that slot thru cover to make a quality shot . .
Warming - Note prism optics have sorter eye relief like a normal scope and that can be an issue for some . Red or green dot optic is better set farther out on your rail than a scope .
MY wife still used a early Primary Arms MD-ADS 2moa red dot on her AR9 fun gun but like me handguns use green dot optics and her AR15 runs with a LPVO 1-8 with a red lighted reticle as an option . I'm a scope guy to on my carbine but I have 52 years hunting with a scope in all sorts of conditions including coyote hunting in near low light with a 2.5-10x42mm nikon . All of our scopes have 30mm tubes and that can help with brightness you see as light fades .
For HD I have a combo laser / light combo on both HD handguns and carbines ..
Optics like the Holosun ARO-EVO and a few other want you to think the solar charging system offers something special but will you keep your rifle in a location to stay charged when not in use .
My wifes old PA red dot gets a new battery every 4.5 years with a brightness setting she needs . My holosun is the same way but it shuts off when not used an shake away so battery last and last and ,,,,,
Good luck