The bar bits internally routed cable dual position versions let you use all the positions on a drop bar. flats your hand wont be in the bar mit.
as far as heated gloves go its the core you need to keep warm. I would get a heated vest and wear good arm warmers, well and I would use bar mitts but to each their own I guess. I have noticed everyone I have ever meet that makes up reasons for not using bar mitts realizes they were wrong once they use them.. They are not a complaint free item I will admit that but the few complaints people ever make are followed by yeah but my hands are warm and dry....