Having played both UO and Shadowbane along with most other MMO's throughout the years, I'd say it's worth it. The engine runs fine, the skill system is fun and the excitement of full loot PvP is as good as it gets.

AV is a small company and will experience growing pains, but they made a good game and have done lots with little resources. I think as the game matures, they will learn to support it better and the content will continue to expand as needed.