I'm slated to get my POC in a few weeks --don't know the brand, but the batteries last about 3 hours. It comes with a car charger. I'm planning on spending a weekend with friends, in a hotel. I use 02 when I sleep and on exertion. So, now that I won't have tanks, I'm looking for advice on the best way to use the POC on the road. I'll be driving for an hour, then in the hotel. Any hints/advice are appreciated. I must admit I am somewhat apprehensive, with no tanks and no big 02 machine!