mediator is not bad an option. from what ive heard grex is a much better one. on an 4000 grex coresponds with the rest of the system via cyberstorm expansion slot unlike mediator that fits into zorro3. the result is much higher throughtput on grex. mediator is limited to about 7mb/s. not enough for much framebufer motion on screen. nevetheless you can use cheap 3d gfx cards, and other expansions, high display resolutions and keep what you need of zorro cards.
edit: in my opinion the cleanest option is med4kdi inside original desktop a4k where it fits nicely. i do not like towers, especially those hacked for amiga pc-like stuff.
