The replacement barrel from TISAS USA/SDS arms has been working fine, but was somewhat bugged that it didn't have the lightning cuts in it. So I contacted TISAS themselves, and within 2 days I now have a replacement barrel coming with the lightning cuts. I've also asked them about offering a threaded barrel for it, so hopefully they see there's interest in that. I had the tool room mill some of the barrel away of the original and as you can see there's zero rifling in there.. I had them mill the chamber away as well just for shits and giggles :D