I reeived my hardened OOW '74 receiver yesterday from my FFL. I am very impressed with the attention the Chris has paid for an extremely low profit-margin process.
The receiver is square (no warpage) and the test pricks from the hardness tester are in an unobtrusive place. The dimensions are right on for a '74 receiver.
Also, Chris actually took the time to bead-blast mine before returning it to me because he "didn't like the look of it after the hardening process". Kick ass service and attention to detail for $35.
I highly recommend this . . . you can't go wrong.
I just wish that ITM/OOW would stop putting that dumb ass logo on the side of the receiver . . . Kind of kicks the crap out of any authenticity.