At the risk of bringing this back from the dead and hurting my chances to get one when they announce I'll share what I found out.
I got NSS and criterion to send a barrel over to Mack Bros and they test fit one. As predicted the remage standard setup fits fine and this one did in fact headspace BUT the "barrel extension" was touching the action internally. Obviously I'm bad at explaining something I can't see in person yet.
The solution to using a RemAge barrel with the EVO is to skim about .010" off the barrel to make a clearance area for the action. That would be the biggest part, not the recess, and just for the barrel to not bottom out on the action when it is headspaced.
Hopefully that made sense and I would like to share my experience to help get the info out there to help those guys out, and anyone looking to build a bUdget rifle like me.
NSS is now telling people this if you call to order a criterion, not sure if other mfg know already