I think one thing you also need to consider for the printer is the printing speed. Most inkjet printers kasi that are converted using Ink All-You-Can System (or Continuous Ink System) takes around 3 or more minutes for a 4R pic, photo quality. So that means in an hour, you can only print 20 photos max.
There are compact photo printers who can print in as fast as 45 sec. Some printers nga raw can print 20 sec though I don't know for sure.
When it comes to customer satisfaction kasi, syempre they want to have more photos printed. And sa tingin ko nowadays, photo booth business is getting more competitive so dapat may edge ka rin talga in one way or another.