GamerDad has written up
an article that reviews all four of BioWare's premium modules for Neverwinter Nights. They've given Witch's Wake a 2.5/5, ShadowGuard a 3.5/5, Kingmaker a 4.5/5, and Pirates of the Sword Coast a 4.5/5. A snip from their summary:
The four modules combined cost just over $20, and provided me with about 30 hours of gaming time for a single run. Add the replayability of different character classes and types – as well as story-impacting decisions in the KingMaker and Pirates of the Sword Coast modules – and I have gotten well over 50 hours from these modules. The quality of modules is certainly very high.
I compare this with the freely available Eye of the Beholder, which is a recreation of the classic game. Eye of the Beholder is about 30 hours long and freely available – and is one of the highest rated modules at the Neverwinter Vault, but like the classic game offers minimal role playing. The focus is on hack-and-slash action against a wide variety of enemies and gathering up loot. I had played this module some time ago, and enjoyed it – but in terms of production values and polish it does feel like a fan work. I replayed again after finishing all four ‘premium modules', and there is clearly a distinction, particularly with regards to the KingMaker and Pirates of the Sword Coast modules, which are superior in pretty much every way to Eye of the Beholder.