Instruct: Classify a given Amazon review into positive or negative sentiment.
Query: Very mediocore bag.

I have this bag which is now a few years old. I bought it for a entry level bag bag to use for backpacking etc., The big problem is that the 20f rating is pretty far off even when using a good thermarest. From my experience, even though 20f is a survival rating, using this bag in anything below high 40f's you will be in for a very cold night(this is coming from someone who likes to sleep slightly cold).Also the zipper only goes halfway down which can make it difficult to get in and out, and makes the bag feel really small.