Here are the 4 different power stations I have tested. The two Anker brand power stations, I suggest for iPad style photo booths with digial sharing only.
So far, the EBL has been the best price for what you get, and at this time, if I was doing this again, I would only purchase this style power station for all of my photo booths. It works great for the iPad booths, DSLR booths and event the Magic Mirrors with or without printing.
If you’re looking at smaller battery packs, make sure you check out this post about the smaller battery packs.