The company I recently started working for bought an Ember for testing. I never mentioned anything about value proposition; merely that it is a viable option as far as resin printers go. Since the software is still in beta, they currently have a different process for loading files onto the printer, but it's not difficult. When you load your file onto the Ember website to convert it to the file type the Ember uses, you have the option to print with any resin you want and the optimum settings are already loaded, put there by the community. However, you can tweak the settings to your heart's desire if you wish. It also integrates with that 3D scanner app, 123D Catch, but I haven't tested that yet. As far as "open source" goes, I'm not a tinkerer, but it is available if you're so inclined.

I've never used a Form1+ so I cannot speak about quality and ease of use, but I can tell you that the Ember "just works" and prints very well. I'm very impressed with what I've seen from the Form1+ as well. A representative from FormLabs was nice enough to send me some sample prints last year; a ring in their castable material, and the "twisted rook" which I have on display in my home.

The company I work for does not sell the Ember. I'm just saying that for the last few weeks I've been testing it, and I like it.