Welcome from SE Tennessee.  I have not been on the Dragon for years, (funny how when you live near, you don't go), but I think you will love your Rocket.  Looks from the picture to be the Touring?  As you can see from my avatar, my touring bike is my Indian, so obviously when I went Rocket hunting, I went for the Roadster.
Triumph makes great bikes.  They sell well in the US, but supply is somewhat limited.  My dealer here in Chattanooga, Pandora Motorsports, sells a bunch of Triumphs of all models.  But they only get one Rocket at a time.  Not because they can't sell them, but because that is all they are allowed at a time. 
Only thing it takes getting used to on the Roadster is getting that huge back tire around tight corners.  Have to use strong eyes and hands technique, and a little body thrown in!