Trying to find out more info on this particular model,I recently bought one and would like to know the differences between it and later models.

Going off of memory because I had one when I was contracting...

As opposed to the Mod1:

Nitride Bolt/BCG not Nickel Boron
Lothar Walther Stainless Barrel - 5.56 chamber
Fore end not free floated and full quad rail
Non adjustable gas system
Mod1 fore end is an inch shorter than the muzzle
Piston isn't easily removable

Pretty sure those are the high points.  Mod 0 is a good piece of gear.  You'll dig it.

Thanks,appreciate the info.
I emailed PWS as well,there is some info on the website.
Hopefully will be here next week,now to decide if this replaces the AA 14.5 rifle or not.

Something to consider is that there are no replacement Mod 0 parts availible anywhere.

I got the very last Mod 0 barrel last spring when I had an issue.  

It's a great gun, and count on it to outperform the AA, but ongoing support may be a problem.