I think pretty much any class could solo to level 50 if you didn't mind the down
times (except mabye rogues). I'm not sure why anyone would want to though as it
would get very boring.

A cleric would have to stick to undead most of the time as our live dd spells
are really bad, especially in the low 40's when your still useing wrath. I
didn't personally solo at all until I hit level 47 when I could pull spectres
solo so really don't know what i'm talking about :)

As for the cleric armor, the only quest I have done is the weapon. Imo the
quest armor isn't very good at all and not worth the time or money it takes to
get it, but that's just my opinion.

Drogo DarkBane
L50 Halfling Cleric
The Rathe

P.S. Halflings look good in purple :)