Hi Toneburst, thanks for your reply, at present I own a DX-21 but love the small form factor, knobbiness, the loading of DX-7 banks(albeit may sound slightly different as you say) and a VST/Standalone editor as a bonus, this would replace my DX-21 hopefully, but I don't want to loose the Solid Bass and other sounds capable by the DX-21, in that case I would have to keep the DX-21, So really yes, can it do the early 21, 27, 100 4 Op thing as well as DX-7 6 Op thing is what I am getting at...
BTW I have found out how to put the banks of the DX-7 onto the PreenFM2 - using the usb stick, I already know and have them via Dave Benson's page the original Roms. So answered that question myself by reading up on this site...