Well, 241 CON at level 30 is 560ish HPs - looking at it that equates to about 1/6th of my hitpoints. I know it's not a huge amount, but it's not too shabby either.
(Numbers are from memory, as the servers are down at time of writing, however I do remember it contributed 1/6th my HPs and I had just over 3000HPs, so 560ish sounds right
).
Obviously, priority for me would be DEX and WIS I think.