The tradeoff in value wasn't worth the time it was requiring, so we outsourced to compose.io -- they've been a good fit price & stability-wise, and feel pretty close to a blackbox for the benefit. If you need a large cluster however, you'll pay handsomely with any of the SaaS providers when last I looked at it. For large quantity work we've moved to AWS Redshift.
There are a few hosted elasticsearch services available (Elastic Cloud, AWS ES, Qbox, etc) which would likely be a better option for the team that needed a hands-off elasticsearch cluster.
I should add that all "hot" data fits in 24g of memory.
Regarding those examples:
1) For RHEL and Windows, paying is not optional 2) Mongo is so buggy most people need to pay for support in production 3) MySQL works well, but don't expect anything more than "forum answers" from Oracle support. Only 1 in 1000 companies paid for support according to the former president of MySQL AB.
Actually, companies are reluctant to pay for support for Open Source products, hence the business model tweaks of Redhat and the Open Core models of Nagios and other smaller Open Source vendors.