Ok, I've been looking at this item on the AH for a long time and I thought it was +30MP not +30 HP like it says here. I'm a white mage so that's why I took interest in it. I guess I should go look again... (O.o)
I'm a Mithra THF but if I came upon these I'd keep them. They rock at farming and soloing, but I can even see use for these in a pt if you have +DEX gear for SATA then use +STR and attack gear just to hit. Actually, that is ideal for me at least. It doesn't matter much if your SATA hits for a million if your whimpy dagger attack hits for 5. :P This way you can always do optimal damage, just do a macro to switch gear.
STR and VIT are nice and all... but being a Mithra THF, this does diddly squat for me almost. Sure, it'd be nicer to hit a bit harder, but I rarely ever get hit, meaning the VIT and the HP+ are just for show... :/