It's great and efficient! We can do a lot with it and I would like to think that we could do everything we needed to do from it for a day or two. I don't know how much the battery would last beyond two days of sparing use but can't know that until you test it out.
The size of it is great for sure. It's about the size of a paper shopping bag, height and width, and a little deeper than one so it can fit in a lot of different places. Important part is to keep it stored upright. It's a liquid battery like a car I think so it's volatile if stored on its side or something.