Stay away from the HD gloves. I bought a pair, they were very expensive and didn't give any heat to the fingers. Maybe I just got a defective pair, but at $185.00 I was expecting electric blanket warmth. Luckily, I was able to return them and get my money back.
Bought a set of Gerbings, they are awesome - so much so I bought the pants, and next spring I am getting the jacket liner. The wires are a PITA when you have the gloves only, makes it much simpler if you have the jacket too. BTW, they are in Tumwater WA.
I haven't tested my Girbing gloves below 19 degrees, but they were great at that temp. I made a 200 mile trip (each way) to visit a friend in the hospital. I picked mine up at the local BMW bike dealer.