Meant to ask you: How do you know it's the fastest? I've seen proposed HP/Torque for it, but haven't seen any track times yet nor top speed listed. Granted, the S50 doesn't have a great top speed, but it'll get there quicker than most in its class...and a few above it.Or, you can bypass both of em, and get a Honda or a Kawasaki.
Truth be told, though, the S50 is a good buy.
Seeing that you have a bit of money to blow, as you're considering the Hog, take a look at the Kawasaki Vulcan 900 Classic. It's the fastest bike in its class, I believe, and it's way more comfortable. 7350 bucks.
I would recommend it over both of those motorcycles, and anything that Honda, Suzuki, Yamaha, or HD has to offer.