tonight i will check what i have selected. as frank says, the STT-FW8G filter wheel has a built in pickoff prism and guide chip. both the main imager and the guide imager are behind the same USB interface, hence the need for the API guider when using PHD2. i thought that the RGH was a yet another thing, like in the STF cameras which have a port on the camera/filter wheel for an external guide camera... but i'm not up on all of SBIG's terminology.
the problem, as always, is that i'm pretty sure that once these updates are applied there's no going back to an older firmware/driver. this makes "non-destructive" testing almost impossible. i wish these guys were more organized about huge changes like this.