July 31, 2013 6:46 PM EDT
I've played both sides, and it really depends on what type of character I'm playing. If I'm playing a thief/assassin/evil type character, I generally go with the Volkihar vampires. I love the castle because of the atmosphere. It really does feel like a gothic castle, and the court is interesting.
The Dawnguard side is also fun, and in my opinion, the final battle at the end is more satisfying on this side. I also love the huskies. The trolls would be cool if they weren't so stupid half of the time and not even attacking enemies.
Overall, go with whatever side you feel most interested in. You could always save your game before making the ultimate decision. This way you can try both sides on the same character and see which one you enjoyed the most.