Vance & Hines exhaust problem - UPDATE

I previously posted about a "pinging or popping" sound I was hearing from my new V&H Longshots I had installed. While I was researching this and asking around, one of my pipes - heatshield acutally - yellowed. The pipes were only on about a month and I had only put minimal miles on it. I also noticed a little chrome peeling off below the yellowing. Long story short - through the help of local HD dealership - V&H made an exception and warrantied the pipes - yes warrantied them - prob due to the chrome peeling off. They put the pipe on the dyno and it was running way too lean. They installed a HD fuel tuner and got my mixtures right. I actually gained 10 horses and about 7-8 lbs of torque. The pipes were currently on backorder so I took the bike home until they come in. I am still hearing the "popping sound" mainly when I go to take off or when cruising in 5th gear and go to speed up. I'm HOPING that the problem is in the pipes - maybe defective in some way or an unseen exhaust leak. Was reading another thread on here where someone else has the popping sound. My bike is EFI and like I mentioned has the fuel tuner and previous Stage 1 performed. So i guess, what I'm asking is this something I'm just going to have to live with or could it be something in the pipes????
Thanks again to all the previous replies on this.

I dont know the weather in your area but I have herd alot of guys are going to the stage 2 even with just pipes and a SE air cleaner kit. Maybe this puts a different timing advance curve in the ecu to cure that stumble when accelerating at highway speeds. I have seen ignition timing that does not retard enough cause this. I have my module set to retard about 8 degrees at WOT and this made a big difference on both the acceleration and detonation problem. BTW, I'm carbed so this may be irrelevent.