Geez, I didn't realize you had to remove the handlebar! I thought it could be done by just removing the outer fairing and radio to gain access to the hole in the middle of the handlebar. Then after removing the stock grip wires, you just fished the power wire through to the left side controller. If I'm wrong then I guess I should just let the dealer install them.
It is entirely possible to install the Heat Demons without pulling the bars or removing the existing internal wiring...I've done it personally, and know several others who have done the same. They supply you with a flat plastic fish tape and if you apply a little lubricant, like silicone spray, windex...anything non corrosive...it's not all that difficult with the fairing off and the radio out of the way. You'll have to grab the fish tape with a pair of needle nose pliers to pull the wires out of the center hole, that's all. I'm not saying it's a walk in the park, but it's not hard either. The Heat Demon wires are not heavy gauge, so space is not a problem, though it's all tight in there. Certainly, if you were changing bars or had to remove the bars for some other reason, that would be the easier time to do the Heat Demons. Just take reasonable care not to pull on the wires where they attach to the heating element.
The Dealer that said the Heat Demons are not as reliable as the HD grips is as FOS as a Christmas Turkey...
I would NEVER put HD heated grips on a bike if I had to buy them. While some have never had a problem, many, many others have. The Heat Demons are reliable, easier to operate, look good, and allow your choice of grips, as long as you realize that the thicker the grip, the longer it will take for the heat to get to your hands. And of course, thick rubber grips will not conduct the heat as well as other materials.