If you consider raidloot.com item search, you'll notice that it places great value on heroic Stamina implicitly. Where 1 hSta equals 15 HP, in searches that include hit points that means that in the typical weighted searches like 1 hAgi = 4 AC = 40 HP = 2.66 hSta. In other words, hSta > AC ! Uhm What!?
So yes and no. There are factors like AA that boost return from stats on gear. And different classes benefit at different rates. ie: Hstamina on a necro with no as boost works as follows. 1 heroic stamina equals 4.375 hp +10. So a +8 sta Aug would give 35hp +80 equaling 115hp just from the heroic not to mention what raw hp it may have. Now once you figure in things like AA and power source etc etc that number goes up. Currently on Bob each point of heroic stam is 21.625 hp vs the base 14.375. I would imagine there are formulas for the other stats as well but I don't know them off the top of my head.
I'm a raid geared warrior and I use the following formula to evaluate type 7/8 and type 5 augs : 1 AC = 1 Hsta = 2Hagi = 6 Hdex = 10 HP While this formula gives me only type 5 Hsta favored augs to use, it gives me a few RoS Hagi / HDex only type 7/8 augs to wear over some EoK augs with only Hsta.
Easy enough to figure for the particular character though. Looks to me like 1Hsta = 36 hp for my bard.