DatoCMS is really impressive, but the fact is developers usually only need a CMS for clients, and clients are going to raise holy hell if the commercial CMS you set up for them 2 years ago goes out of business.<p>So while all things being equal I'd prefer to choose the indie business, having been down this road before I am wary. Especially since the CMS is not a layer on top of git, so getting content out and ready for another solution will not be pretty.
I just wish there was a content editor for GitHub a little better than <a href="http://prose.io/" rel="nofollow">http://prose.io/</a>.<p>Prose is great, but not good enough for HTML, customization or other static site generators than Jekyll.
I learned about Dato a while ago and was pretty impressed ever since. Unfortunately I don't really have a need for it right now as I rarely do that kind of client work, but if I was in such a situation Middleman + Dato + Netlify would seem like a fantastic combination.