As durability "feats" go. The closest quantifiable comparison between Ktonian's and the Hulk would be how they dealt with aircraft fire.
An A-10 GAU 8 30mm round hits at about over 200k joules (need to someone to validate my math tho) and a single pass (looked like multiple hits tho, like 3-4 at least) knocked Nam Ek (the bigger, stronger and I'm assuming tougher Ktonian) on his butt, made him go "Urrrrh! Ugh!!" and kept him down on his knees for over 10 seconds.
http://youtu.be/Uwgv5FayZD8
(0:25-0:38)
By comparison. Hulk took at least a hundred rounds if not hundreds of rounds from 10 seconds worth of continuous fire from a F-35 GAU 22 whose 25mm rounds hits for about 100k joules (again, math check pls). Funny thing is, F-35's only really carry enough ammo for 3-4 seconds of continuous fire. :-p but eh, movie physics. He took it like it was literally nothing. Like spitballs at best.
(See clip/timestamps I posted earlier)