Both Rinehart and Vance & Hines do the below the swingarm thing with the front pipe. Earlier attempts at true duals sent the rear pipe out the left side and the front down the right side. Our 2005 Ultra could fry the inside of my thigh even on a cool day.
On the CVO, we get plenty of heat with the stock system. There are days I cringe just at the thought of getting caught in traffic. I am hoping the new under the frame helps take some of the heat away. By design, HD engineered the rear cylinder to stop firing in hot situations. I have not noticed any difference.