My understanding here was that the OP wanted to play the actual retail CD games. I think every TG16 emulator these days can read TG-CD's through your PC's CD-ROM drive, so it's sort of like a big console (Hell, build a computer in a case like this, and with the right emulators, you could ditch your SegaCD, TurboGrafx-CD, PSX, etc).
In theory, you'll still have to pirate the Super System 3.0 ROM image (or suffer with MagicEngine's replacement), so I guess it's not a perfect solution, but it's basically free.
--Zero