I have played a solo character with Stealth. Missy has it, although she rarely uses it.
Why? Well, stealth gives you nice bonuses to your hits and damage. Makes you a killing machine, really. And you can avoid being noticed when you want to.
So what's not to love? Well, you're never noticed (except for certain infra-red-sensing NPCs). Which means that the creature you're trying to attack may just keep walking or swimming away from you. And remember... if your stealth is high enough, you can attack and remain hidden. So that Colanth keeps swimming around, wondering why it's suddenly bleeding...
I found that in a party of six, I left one character "un-stealthed" so that combat didn't consist entirely of "Hey! Come back here and let me hit you!"
'Course, if avoiding combat is your primary goal, there's a lot to be said for it...
