Regarding the film for the internegs, from what I've seen they are all about if not exactly the same. Given the volume of the niche, there may be only one actual manufacturer.
I started with Pictorico and have third company's beta product here for testing.
I will use Inkpress for the moment at least because that is what the experienced pro I'm working with uses. (For his work, see http://tychobrown.com/) He uses it because of its wide availability in lots of different sizes. He has no ax to grind here and a good technical background. The price is also good, and I suspect price and availability are the main variables. I don';t think it's going to have any significant impact on this project.
Paul