I initially bought a green laser on Ebay for my PS90, prior to getting the gun itself. The green laser was so, so bright. TOO bright! It actually lit up a dark room completely (like a flashlight), and U could also actually see the beam itself in the dark. At household distances, it hurt your eye just to look at the green dot on the wall. Outdoors in the daylight, it was visible past 100 yards, and over 800 yards at night (probably further, but I had nothing further away to shine it on by my home).
I did a lot of research, and found that I didn't think that green laser was safe for my eyes for what I wanted it for (indoor use). So, I sold it to someone for about the price I paid for it.
I then picked up a BSA red laser for my PS90 - It does what I wanted it to do - I have it set at 7 yards for internal home defense distances - and its visible even in the daytime at that distance.
It has a master on/off switch, or a pressure switch. I decided to use the pressure switch, which I have velcroed to the front of my PS90.
The BSA laser only cost me $29.99 at Gander Mountain, and it can be had for that price or less at many other places. I'm not sure how it would hold up on a high recoil weapon, but for the low recoiling PS90, it holds its zero well. I haven't had any problems with it. Its also fully adjustable for windage and elevation.
I May have kept the green laser and zeroed it in for 100 yard use at the outdoor range if I had more room on my PS90. It would have been a fun outdoor toy. But with the Eotech, flashlight and red laser I already have mounted, there really wasn't anymore room for the green laser.
Anyway, I'm very satisfied with the BSA laser, especially for the price. And, I did take the little BSA logos off each side of the laser, to make it look better :wink:
I'd easily recommend this laser for the money. Sure, there are nice red lasers out there for much more. But, I think this one is worth considering if U are broke after buying your PS90 and all the other stuff that goes along with it