I never had a mediator but I wanted one for a long time to make a 1200 tower. If I have to switch monitors or flip a switch even,just to use amiga screen modes or play games, that seems like a huge PITA just to get a 24 bit color workbench. Sure you can use a network and sound card too but again, hassles. Instead I'm going to make a dedicated amiga emulation pc/aros machine. Drive c will boot windows in the background, using amiga os3.9 as the shell. I've done this before and it works great. Then you can use amikit or amiga in a box or amisys. All games work, everything works.
You'd never even know windows was underneath if you set it up well.
I'm going to get the new mouse/keyboard from amigakit for this machine.
My drive d: will have aros. I use the bios to switch which drive is the boot drive... Easier than dealing with lilo/grub and so on.
Total cost? Like 100 bucks including a 2.5ghz slimline dell with 1gig ram, and the boing ball keyboard/mouse from amigakit. This computer can also run windows or linux... or haiku also.
I prefer to do this for my hobby computer, everyone I know who did a mediator with a 1200 regretted the expense and hassles...
Steven