Neither of them will be any more stable than the release version.
If you are not a developer, you should use the public beta channel.
However, I don't advise installing it on a main machine.
Betas are still in testing, and you will more often than not be worse off than you are now.
I had installed a beta on an external drive, and the installation had major issues.
If I'd installed it on the main drive, I'd have lost almost everything.
Depending on the issue you are having, the risk may not be worth it.