I had heated grips on another motorcycle a couple years ago. I don't know what may be available for the Bonnie, but I'll bet if you have any reason to doubt the quality of generic no-names..... Harley Davidson would offer some that fit our Bonnie's 1" bars, and they would likely be a good product.
That having been said, there are in fact some gloves out there DESIGNED for heated grips. Apparently they channel the heat from the palm to the rest of the hand.
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The heated grips on my BMW were all but useless UNLESS I had the hand guards mounted on the bike. Between the hand guards blocking the cold wind and my heated grips, I was able to use thinner gloves that allowed the heat through to keep my hands warm(er).
I tell ya what though, when the weather is changing and ya gotta ride home in the cold after a day of needing only a summer jacket, heated grips can be likened to comfort food...... they 'help' you to feel better under adverse conditions.