I bought a premium subscription recently and was hoping that EN would make my rather massive research article collection and laboratory notes more organized. The concept is outstanding (read as it was put together very proficiently), but the team/product managers responsible for keeping it bug-free are likely not doing things right. I was very impressed with the graphic interface and decided to organize all my notes, articles, data, and photographs of older handwritten transcripts into EN! That was certainly a big mistake on my part...
For the second time in a month I've had to do 2 things (I installed EN on my MAC OSX snow leopard):
1. Could not get the main user interface that has all my material in it to show up; I only was able to make new notebooks from the menu options. After reading through some very helpful user posted solutions here, I had to delete library folders, restart EN, and then wait for it to download all of my notes to start working - which takes a very very long time, and defeats the purpose of having all my material constantly offline to refer to. If I have to download all of my notes 2x monthly, then I suggest that EN not accept money from customers until they fix issues like these, or put the issue in as part of the very slick features (with Apple-like design marketing graphics) so that potential customers can know of this before parting with their money.
2. Oh, the other thing I did again this past month was to send a report of the problem to technical support - and as before, I have not heard a word. Zilch.
So, my own opinion after paying for EN - it is a great concept, and has a team selling it with brilliant graphics, fonts, icons and color usage so that it looks like the real thing. But I think it is too flaky to entrust a whole lot of research material and notes (that most people value greatly, since they represent a lot of work). It also lacks documentation and customer service. It is very good at processing credit cards for subscription, though. They must have hired good people in a few departments. They also have a few great people masquerading as experts on this forum who will defend the sloppy code as something that you should not take too seriously. If you are a free user (like I was), please continue to be free - dont end up paying for EN like I did (any pun is definitely intended).
At the very least, I hope my post spurs someone at EN to talk to whoever is in charge of the code for Mac OS libraries and offline notebooks. In the meantime I am migrating everything back to good old-fashioned folder based organization with links to materials in Adobe and a word processing document.