50MB uncompressed - that's very impressive. About the same as the full ClassicWB 3.0 packages! And there using stuff from years ago!
This OS is sounding better and better. If it's as accessible and as easy to manipulate as the old workbench was, I'd seriously consider setting a OS4 machine up on new hardware. Happy with WB 3 on Classic.
Another decisive factor for me will be it's ability to web surf, e-mail etc with major security benefits over similar tasks performed on mainstream windows. A cleverly integrated "Classic Amiga" emulator would also sway me.
I'll always keep a PC handy however; they're SOOOO cheap for all the power they offer it doesn't make sense not to have one hanging around.