dunno.
> It mentions CD-ROM and DSP on the case, is it possible to connect a CD-ROM to the unit?
For the CD-ROM: dunno. Don't really know for the DSP either, but my Profighter got a DSP chip like the Mario Kart Cart has built in on its mainboard, it doesn't really do anything although (DSP games don't work, most likely the chip is just broken).
> What is the purpose of the D25 connector at the back?
Simply to load ROMs to the unit from your PC via the parallel port with programmes like SNESTool or GTool.
> Finally is it worth getting a Gamestation instead of this unit?
Maybe instead of the 24 MBit Profighter, but it'd be a much better idea to purchase a 32 MBit SWC DX 2 for the same price as the Gamestation costs.
I got a Profighter Q (32 MBit version) myself and it really is a fine unit. It does its job pretty well and I never had any problems with it.
-- Matthias