http://www.atncorp.com/DayOptics/ReflexSights/ATNUltraSightDigital
Yeah, it's ugly.
http://steveandrhonda.clearwire.net/Gunstuff/MKII'sL.JPG
I've been using an ATN UltraSight Digital Reflex sight for the last two years. I shoot rimfire gallery (545 +-5 in a 600 series), with good open sights. I've been in the 560's using this nicer dot sight this season.
It's the best thing I've used yet. Allthough it's a bit (OK, a lot), heavier than some of the others out there, it is clear and bright, but when light is low, turning the intensity down when on 2moa, the dot is so small you can barely see it. I turn it down to almost it's last setting for slow-fire, but I bump it up twice for timed/rapid. I have thousands of rounds through this platform without one issue with the sight. I can't say that for many other cheaper models I have tried or have seen on the line. The Big BSA's are a waste of money. These cheap Chinese made ones for $39.95 are even worse. They just don't last. I've got a Tasco ProPoint tube style that still works. And my nephew has been using a Simmons with a 3moa or so, that has lasted quite well.
I'm not sure I want to switch to the ATN UltraSight Digital Compac because the dot only goes down to 4moa.
I thought I wanted to switch to the newer UltraDot /LT,
http://www.ultradotusa.com/ultradot_dist_blue_009.htm
But a buddy bought one a couple weeks ago and couldn't get it to hold sight properly. -So that one is still under review.
The Doctor is the cat's meow! But pricey. Still only a 3.5moa dot. With degrading eyes, a 2moa dot won't do you any good anyway.
http://www.trijicon.com/user/parts/parts_new.cfm?categoryID=13
Back to that ATN UltraSight Digital... No special tools to mount it. (A quarter for the screws), No special tools to adjust it. (A pen knife screw driver), You don't have to remove the sight to change the battery. (same quarter)
Can't say that for some of the newer smaller units out there. (Sure the BSA/Simmons/Tasco other tube style have these same features, but some of the newer units require metric allen wrenches and a dial thingy to adjust them. Sorry, not something in my Bullseye box.
-Steve