The newest release of GOS is 5.0.133 at adaptec's website via snapserver.com.
http://www.adaptec.com/en-US/support/snap/
Interesting, I cannot find a link(did not look really hard) to it at Adaptec's website on the front end.
The previously released version was 5.0.125 which had something wrong with it. I think it was an installation problem with some models.
Keep us posted on 5.0.1 and what the pros and cons are.
bitor