By way of background, I have Hondaline heated grips on my NT700. I have previously installed BMW heated grips on a BMW and 2-sets of KTM grips on KTM Adventures. I attempted to install the Hondaline grips, but ended-up having the dealer complete the install (I'll explain).
Firstly, I'll answer an un-asked question. If I were to choose between using heated grips and heated gloves, I'd without question choose heated gloves -- in cold weather, they are much better at keeping your hands warm. That said, I use both (not at the same time). I generally use the heated grips at times when it's not cold enough to require heated gloves, but when a little heat from the grips can take the chill-off.
Now to your questions:
1. I think the Hondaline grips are grossly over-priced and poorly constructed compared with factory grips I've purchased for BMW and KTM bikes. The Hondaline seem to be a low-quality plastic rather than a rubber grip and the series of required harnesses is a inelegant -- the grips may be good, but I don't like the look, or feel. However, they work very well and the controller is exceptional. Neither my BMW or KTM grips had an electronic controller -- they used a 3-position switch, or rheostat. The Hondaline controller gives you several heat settings and electronically shuts-down the grips if the alternator isn't generating enough power.
2. This install should be simple (once you figure-out which sub-harness to use). It's a plug and play install (if you purchase all the required parts), but a clunky one. I normally do my own maintenance and began the install. Mounting the grips and controller is straight-forward and simple. But, when I removed the fairing to locate the accessory plug, I found the plug wasn't where it was supposed to be (don't confuse the accessory plug with the nearby red diagnostic connector). After an unsuccessful search, I decided to take the bike to the dealer (with most of the fairing removed). The dealer had their head mechanic look at my bike while I waited (as I had removed the pertinent fairing parts) and he couldn't find the accessory plug either (it wasn't where it was supposed to be). He had already installed grips on another NT700, so he knew what he was doing. I didn't have time to mess with it, so I left the bike with him. He said he'd either find the connector, or splice into another wire to make it work. He quoted 1.5 hrs for labor. I could have done the same thing, but didn't want to worry about voiding the warranty if I had to splice wires. Ultimately, the mechanic found the plug. He said it wasn't where it was supposed to be -- it had been pulled to the opposite side of the bike and taped completely over with other wires. I'm sure part of his explanation was to minimize my embarrassment and justify the 1.5 hrs labor (it shouldn't have taken that long considering I already removed the body parts and would re-install them myself). So, if you're in no hurry and don't mind the possibility of searching for the connector, I don't think you'll have a problem doing the install yourself.
3. I also ride dirt, dual-sport, and adventure bikes and don't find non-glued grips satisfactory. I've used alcohol and hairspray in the past, but using glue is superior. Yes, heated grips can warm and loosen SOME grip glue. Some guys use Super-Glue, but if you don't line things up correctly, quickly, you have to cut the grip off and try again. At the advice of my KTM dealer, I use Threebond Griplock. This glue is made specifically for grips. It dries fairly quickly, but gives you time to line-up the grips and does not become loose when heated (it requires 24-hours to completely cure). Some after-market heated grips ship with Threebond.
Overall, I've been very pleased with the grips and would install another set if these failed. Hopes this helps.
