I've used Magtech primers when reloading, but I've never used their loaded ammunition.
I read that the military measured CUP (copper units of pressure) but reported the results as PSI, which made it appear that the 7.62 chamber pressures are milder than those for .308 (which is measured and reported in PSI), and in reality, the military 7.62 and civilian .308 ammo is about the same, with chamber pressures usually in the 55,000 to 60,000 range.
http://www.surplusrifleforum.com/viewtopic.php?f=76&t=39614
Note that there was considerable push-back against this position because it flies in the face of what the internet knows to be true.
In the context of your MagTech ammo post, I also found the following excerpt from that linked thread to be interesting.
"The guys at Tioga Engineering once blew up an action testing some Brazilian 7.62 that the factory had accidently loaded with pistol powder. They calculated it was over 200,000 psi."
That makes me think it may be safer to shoot my home loaded ammo than Brazilian surplus ammo.
While I love reasonably priced mil-surp reloading components, this comment also put me off shooting mil-surp ammo:
"I am comfortable in saying that any commercial rifle will safely shoot any decent lot of military or commercial 7.62/308. I say "decent" because some military surplus ammo was taken out of service becasue it was defective or erratic. I recall a lot of one million rounds of canadian military ball ammo was that was taken out of service becasue it was found to be defective. It was purchased by a bidder that was supposed to destroy the ammo (pull it apart to salvage the componets) but it wound up being advertised for sale in ShotGun news."
I've read several other similar comments pertaining to mil-surp ammo from Turkey, Greece, South Africa, etc.