I’m running iOS 12 beta and it’s been stable so far. But I’d never run a Watch beta unless I was a developer. Like you said the fact they don’t offer public betas should be a clue not to run betas unless you absolutely have to.Anyone who isn't a developer with a separate device for testing is taking a huge risk by installing a watchOS beta. It's crazy to me that non-developers are installing these developer betas on their watches. The fact that there are never public betas of watchOS should be enough to dissuade people, but apparently not.