I know the Op went ahead and got themselves a Dyna which is an excellent choice.
As for the Sporty, it really comes down to expectations. For hopping around town, short trips on country roads for ice cream, it's really a nice machine to play with. I do have a gel pad with the factory seat and can play for most of the day. The peanut tank allows me to stretch my legs during a fuel stop. As the rest mentioned, placement of foot controls and bars can make a huge difference too.
If you wanna ride with your friends on the interstate for the weekend or day trips on a solid mount Sporty, you may find yourself a bit fatigued. Windshield helps but, the only time I ever use one is during the cooler temps.