Things I liked: It is small and light. So nice to not have to pump up my gun. The handle is big, so it is easy to control the fill on your gun.
Things I would have changed: You have to buy the fill valve to get it filled anywhere. It should be included. It also takes a wrench to change from the hose to the fill valved. I got around this by building a female female foster fitting hose and I just leave my fill valve in all the time. Also, the gauge doesn't show pressure unless you are filling the gun. So it is really hard to tell how much air is still in the bottle. When it is all the way full, you do not open it wide to see the 4,500psi because you will blow your gun.
What others should know: You can get paintball tanks that might be a little better in some ways. You would still have to build the hose for it in most cases. If I had it to do all over, I would go to a paintball shop and talk over what I was looking for before buying online. I am really glad to have this tank up and running now.