Good DLC. It's only flaw being quest line length, which is unfortunate since I actually found it interesting. Anything involving the Daedric Princes and Oblivion is good in my books.

How short is the questline?

Best of the three for Skyrim, followed by Hearthfire, followed by Underwor... Dawnguard.

Not nearly as good as Bloodmoon was for Morrowind though. But I still liked returning to Solstheim