I have the I.O.R. M2. The version for .308 is the M1. Mine is for .223. They are a fixed 4x
I like it. It seems built tough. It's not light, but it isn't very heavy either. Has 7 brightness settings for the illuminated reticle. The lower ones aren't very visable, I guess they'd be useful with nightvision. The brighter ones can be seen well, but after the sun has gone down.
The optics are very clear. Nice glass. It could be brighter, but it is a 24mm objective after all. For the size of objective, it is pretty bright. Just don't expect it to be as bright as a 40mm objective made by Leupold or Burris.
FOV is better than my Burris on 4x. They've done away with that yellowish tint. That was due to the coatings they used to use. The clicks are very positive, very nice. The windage adjustment is in 1/2 mil clicks out to 10mils either direction. The bullet drop compensator is marked from 1 for 100 to 8 for 800 meters.
I have the dragunov reticle. I'm a big fan of this reticle. It has the range finding slope for a 1.7m (5'8") tall target out to 1,000 yards. Has windage marks spaced 1 mil apart. They have the close quarters combat reticle, as well as that NATO reticle. The NATO one is more crosshair like, but still has the range finding.
Some people love them, some people hate them. So far, I really like it. But I have not yet had the chance to test the BDC at various long ranges to see if it is really what it says it is. Other people have posted that said the BDC is right on. So, I'm hopeful. It is calibrated for NATO loads. So mine is calibrated for the 62gr NATO. The .308 is calibrated for the 7.62x51mm NATO load, which if I remember correclty, is 147gr?
IOR also makes the "super 30" which is a 30mm objective lense. It looks more like a tube. It is a fixed 6x, and is calibrated for .308. It costs more, but should be better. Only problem is, due to the 30mm lense, the body is 35mm. So you must use the custom IOR rings that comes with the scope.