Just sold my bar mitts. They work, but as someone already mentioned, you're limited to the hoods and they can be a pain if your gloves are bulky. Nothing ever worked for me below 20 degrees except the bar mitts. The trade-off was always dexterity for warmth, then I started using these:
https://www.ventureheat.com/winter-s...ve-liners.html
I found them on amazon for about $100. They're worth every penny. A few months later I picked up an open box pair for about $50. I wear them with softshell gloves - isotoner ultradry and seirus mtn challenger gloves. No issues down to 8 degrees. I'll test that again in about an hour, it's 2 degrees out right now. On medium I've used them for rides that lasted 4 hours. Now that I have 2 sets of batteries if I was stupid enough to go out longer than that I'd take the other pair of batteries with me. Had them over a year now with zero issues.