I bought this for our upcoming camping trip because we need a solar shower bag that we can put in our portable shower. I decided to test it out the other day because I wanted to make sure that it was going to work before our trip. It was very easy to fill with water and made no mess! The temperature gauge is accurate; however, you can feel the bag and tell how warm the water is going to be. I personally recommend leaving it lay in the sun for around 1-2 hours, but I have heard that some people heat it up over a fire (it would be faster that way). The water comes out easily and at a steady pace. The 5 gallon bag will last roughly 5 minutes which is plenty enough time to rinse off and go back to enjoying your trip. It is easy to keep clean and dry which I highly recommend because you do not want bacteria growing in your shower bag.