I purchased these for my grandmother who has Raynaud's, and I tested them out first to make sure they work. I fully charged them according to the instructions and turned them on high heat...while indoors. I let them warm up, and they only got warm. After about 10 minutes, I felt the heat start to dissipate. I know they are only liners, but again, I was indoors. Additionally, for $130, it is not made of quality material. I cannot expect these to last for an extended period of time. Lastly, the wrist area is indeed bulky, both on the battery side on the bottom and decently so on top where the on/off button is located.
I did my homework, going into stores (which none seemed to carry "heated gloves") and also comparing different models on Amazon and here on this website. Ultimately, I really had higher hopes for these gloves, especially for the price. I would expect to find these at Walmart for maybe $40 or $50.