What is your hourly rate? How many hours would it take you to recreate even a subset of this functionality? If the answer is "more than half a day" then assuming typical hourly rates you are better off buying. There's a certain cognitive dissonance here, nobody wants to pay for anything but most of us here earn our livlihoods on people (in one way or another) paying us for the software we create.
You say it like releasing a paid-for product is a bad thing?
I'm currently working on a project and would've happily paid for this if I'd seen it at the time and it met my requirements. Currently I'm using CKEditor and happy with it but I would've paid to get a simpler/sleeker product without hesitation.
Having said that, I couldn't see image uploading and browse (of uploaded images) in the demo, which would be a deal-breaker for me.