I've used V&H for the past 10 yrs on both of my HDs. I love their customer service and any problems I've run into (very few), they sent me replacement parts no questions asked. Heck I even sent them an email asking about reusing the torca clamps on my mufflers and they told me a new set was in the mail, free of charge!
I've seen some Power Duals that are on e-bay that are used and the seller noted scrapes right where we are talking about. I also saw a SG being backed off a ramp at Biketoberfest and when the back tire came off the flat part onto the sloped ramp, my gosh I thought the Power Duals were going to scrape!! It seemed like it was only an 1" or less clearance.
I'm still keeping an eye out for a nice used set of Power Duals for my 09 RG.
Ride safe and have fun.