Tried out my new gloves today for my 40 mile ride to work. They were pretty inexpensive even at my local Yamaha store. (approx. 34.00)
Left the house Christmas eve at 40 degrees and using a thin cotton glove liner inside the Joe Rockets kept my hands and fingers warm all the way to work where it was pretty much low 40's the whole ride traveling at 50 to 70 mph. Did also hit some high winds up on the freeway. These gloves do not offer a lot of protection but they do offer some and can be tightened down snug with the velcro strap. I would guess they would be decent for down to mid 30's at freeway speed.
Not sure why they call them sub zero but for the money they are great gloves and I am happy with them. I will still carry a spare pair of riding gloves as these are pretty bulky for riding and will just be used for the cold mornings.