Been using MemSQL for a enterprise-level financial services client since mid-2017. We have this in production and are running it in a multi-TB cluster. We've not seen ANY of these issues here and are heavy, crazy query users. Their support has been nothing but on-the-spot and very helpful.
I totally admit that the inconsistency might be a result of misconfiguration by maintainers at my company. That being said, being able to shoot yourself in the foot so subtly and badly via configuration seems like a pretty strong anti-feature.
Since you aren't sharing any actual details and are switching between blaming the product to blaming your devs and config (where no product can magically keep you from breaking settings), your comments come across as rather disingenuous.
Why not share a clear example of exactly what happened, or post on their forum with details, so we can all judge for ourselves?