I currently own a R3 Classic, and love the bike. Prior to purchasing the Rocket, I owned a Vulcan 1600 Classic which to this day is the best (and favorite) bike I've owned. Why? Primarily due to the comfort and dependability of the Vulcan. Had it for almost 7 years...never in the shop once or left me stranded. As well...was the most comfortable bike I have ever ridden.
As of late I have been considering selling the R3 and getting a Vulcan 2000. The main reason is that I am tired of dealing with minor issues (or what should be minor issues) that are not covered by Triumph, but should be. Just spend some time on the forum and you'll see recurring problems that just don't seem to go away, and that only some Rocket owners have success with getting Triumph to cover the repairs. Plus, there are so few Triumph dealers around that should you have a problem on the road...good luck finding a dealer...or finding one that has parts in stock. Not the same with the Kawi...dealers everywhere.
Additionally, I like to customize my bikes..and there is little you can do with a Rocket. There are multitudes of things I can do with the Vulcan to make it "my own".
Again, not asking for any flaming commentary back at me. I love the Triumph, but am not a die-hard fanatic. Yes...the power is great, but I'm not one of "those" riders who need to get from HERE to THERE in 2.9 seconds.
Like another member stated...ride both, then make the decision. Only you can decide which you like better. Best of luck.