We do a lot of QA in-house before going to BETA. Some products never go to a BETA at all. The builds represent our internal qa and bug fixing before ever reaching BETA.
When we release it will be version 1.0.0. We would like to have longer lasting beta tests, but there is also a strong desire to get this functionality into the hands of our users.
The reality is that we have be developing with and even using the framework builder to develop the next version of Powerstore for several months at this point, so it was actually pretty stable before it ever got to a BETA tester's hands.