For the harddisk emulation I use hardfiles with SFS and that's fast. Formatting in Shapeshifter is almost instant.
I read somewhere you need a rom that's 040 compatible for best speed. I guess your Quadra rom should do the trick though. Can't help you much here...
I succesfully used 7.5.3, 7.5.5 and 8.0 and System 7 is faster.
Maybe someone else can help on other things!
