Yeah, be careful. I signed up for the beta and decided no it is not for me but once I signed up it downloaded the beta immediately and the only option I was given was install or delay the update which I did twice and slept past the 3rd time where I now have the beta for OneUI 6. I contacted Samsung support before the beta installed and after over an hour they could not figure out a satisfactory response.
So now the only way to get back to a stable build is to reset the device and roll back using smart switch on my PC. I was trying to avoid this last step.
So far I don't see a lot of big changes and it seems mostly stable. I have already had a few bugs here and there including UI restarting, etc.
I will update what I decide to restore my device or continue with the beta.