Fellow GTers, As always, I come to you for advice. Finally got the lower for my AR Frankenstein build and I was looking for a laser under $100 that can fit both my AR pistol (it would be the only sight on this pistol for now) and can also be mounted on my home defense Glock21 if needed. I see a bunch of discussions between red and green... It seems green can be seen better and is also more expensive. What worries me is that most have really bad reviews in terms of holding zero after shooting. Any decent ones you have experience with??