All the "experts" here have very differing opinions on the two. But all experts would probably agree that you shouldn't let either decide for you.
Seeing as both are roughly $500 I would highly suggest going with the dealer that will better be able to serve you for the long term. Which one has better reviews, and better service department?
That is how I would decide.
FYI, I believe ozone is better than UVC... however, you could easily add ozone to the Sundance.