It’s true we tend to push our customers towards the latest release, but we have many containers running different versions. The only servers that absolutely run on tests-passed are try and meta.
We usually have a good idea when we are introducing a commit that is risky (for example, a big feature like translation overrides) and we delay deploying all the sites before introducing the risky stuff so that we can run them for a few days on meta/try before possibly breaking for our customers.
Our enterprise customers can run whatever branch they want and even choose when to deploy their own sites via a control panel if they like. They can also provision a staging instance to test their code against.
We prefer to manage it and keep them closer to a stable release branch (with the exception of security fixes.)
Other stuff I probably should have mentioned in my original post:
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All customers get a CDN for added front end performance
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We do migrations for customers if they commit to a contract
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We also do frequent backups and keep them off site
The chances are, if there is something I didn’t outline that we provide it! Just ask us 
This was just an off the cuff response and not a detailed grid of our differences.