@amiga2000
The prerelease it out since time :-) It was free for EarlyBirds. Now if you buy an A1 (any also a Micro) you get OS4 prerelease until the final release.
@Matt_H
OS4 is rocks solid, sometimes i don't reboot my A1 for days :-) So if you have stability issue it is a vcore or installation problem. have you got the first update installed? Check Intuition base or AW.net (it is the official AmigaOne webportal) to find many threads about vcore. I have a 1,74 for my 1000Mhz G4.
@all
Enjoy the update! :-D