Once the traditional operating system has booted it's as easy as hitting F4 to toggle between HyperSpace and Windows Vista. The switching is done quite well and extremely fast. When accessing the traditional OS with HyperSpace Dual, HyperSpace will shutdown and cannot be switched back without rebooting.
HyperSpace currently lacks features like a photo viewer, music player, DVD player, VoIP client (such as Skype), or some of the other programs that can be found in other lightweight Linux environments like SplashTop. HyperSpace could also use some additional configuration features like adjusting the screen resolution, time before putting itself in stand-by, and controlling the theme and other environmental options. There are also no tools within HyperSpace for the experienced Linux user like having a terminal, since this is a very stripped down Linux environment.
That about covers the functionality found in our pre-production versions of HyperSpace Hybrid and HyperSpace Dual. Phoenix Technologies also advertises power usage optimizations for the HyperSpace environment, but this feature was not found in the builds we were using. We are told that HyperSpace will be easily updateable, but we have yet to receive any information surrounding its updating mechanism and whether it can be done within the HyperSpace OS or must be done from the traditional OS such as Windows.