Tons of replay value, fun, but the mechanics are horribly annoying.
The great aspects of this game:
Tons to do, so replay value is high.
A variety of builds to go with (some of which are useless though).
Towns are very different and enjoyable to explore.
A follower system that does not blow mammoth booty.
The crap of this game:
The UI is utter poop. SO, SO, BAD. (console based)
Caverns/Dungeons grow very repetitive.
Money/Skill Grind is a cheap replacement for game difficulty.
Shout System is a gimmick with little to no usefulness.
It's posted at around $40 online (as of Feb. 2013), which I would say it worth it. The add-ons, I couldn't tell you about though.