The Oktagon 2008 uses very expensive and hard to find ZIP package ram. The GVP HC+8 uses very easy to find/cheap 30pin standard simms.
Oktagon = 8mb max onboard
GVP HC+8 = 8mb max onboard
A2091 = 2mb max onboard
If you find an available GVP series 2 HC+8 controller, any rom revision above 4.4 will allow 2gig scsi harddrives and cd-rom without hassles ( this is my experience anyway )
Az