I chose the Iron barrel because it seemed to me the AVL was in intermediary motor. For the most part the AVL has been reliable, but there is an elderly guy on here, I think he calls himself Uncle Ornery, who has been through 2 sprags, and several other problems. But he seems to beat his bike, taking it down rough dirt roads etc. I am sure a properly cared for AVL would be fine.
I chose the Iron barrel because I wanted the vintage Enfield experience. If i had a choice today between the AVL and the UCE, I'd pay the small premium and get a UCE.