Does anyone out there have some experience with atn holosights.  any info regarding quality, mounting, performance etc.  would be greatly appreciated.

I'd like to know the same thing.  BTT

I've handled one of the ATN "Digital Ultra Sights" at my shop... I came away unimpressed.
The ATN is made in Belarus, so its optics and quality are typical Soviet bloc - ugly, rugged and IMHO not up to the standards of US commercial equipment. The lens is small diameter and not "optically clear" and the reticle is relatively dim; I can see washout problems waiting to happen. I'd liken it to EKP-8 "Kobra" guts packaged in a more streamlined body (I didn't like the Kobra, either). Given the $189 street price of the digital Ultra Sight, it's a short hop to something of real quality, like an OKO or an EOTech. Or if you're not wedded to the "tubeless" design, any of the inexpensive wide-body (30/42mm) red dots should do the trick for 1/3 the price.

I have a lot of experience with the ATN holosight as I've had THREE.  The first had a blurry reticle..and felt cheap...[returned for replacement] the second, reticle ok, but turned itself off after every shot [shorted out][returned]...the third looked ok and I gave it away as a gift as I didn't trust it. The ATN mounts to any weaver rail but doen't feel secure.   I spent more money and got an EoTech 552 Holosight.  I should have done that to begin with!  

Don't buy one unless you can see it for yourself.

I love red dot sights, and I've tried a few of the low and medium market jobs.  The questions to ask is:  IS IT PARALLAX-FREE?  The low-end red-dots aren't, and this means that if you don't position your eye in exactly the same place everytime, the dot will shift also... VERY VERY BAD.

After that, consider dot size (anything over 4 MOA isn't much good on a a rifle IMHO).  Clarity of the dot is important.  Variable reticles is nice, but unnecessary,

I have a Russian Kobra sight on my AK, that I like very much, and its a solid post-Soviet bargain at $110.  I also own a OKO and an EOTech.  These are great units.  I have yet to see a low-end red-dot that performs as well as these.

Hope this helps.

[edited for typos]