We have not upgraded in some time due to the same fears - to the point that we also did not renew our support agreement as there were no builds that we could update to that wouldn't have some surprise issue one way or another. The continued cadence of adding new features WHILE triaging bugs is not working because there are no stable releases in some time.
We are a small provider and cannot afford hiccups in software that was sold under the enterprise moniker but does not withstand enterprise testing when released to the public. It cost us too much business in the past to take the chance further. The overhead to running multiple servers just so one can act as a test-bed does not add up either, let alone the client aggravation and man-hours involved in keeping things together.
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