I'm a bit surprised that there hasn't been more discussion about S-100
machines. In particular I would point out the Morrow Decision 1. It's
DJ-DMA floppy controller could handle 8" SSSD thru DSDD, and both
soft-sectored and hard-sectored (NorthStar) 5.25" formats and a separate
hard drive controller was also available of course. Later variations even
had a switching power supply.
Not strictly a CP/M machine (though probably 90+% used CP/M or variation
thereof) and CP/M came standard with the machine. Morrow even provided a
UNIX-like OS, the name of which escapes me at the moment (Micronix maybe?).
With the addition of an 8086 S-100 board it would certainly run a plain
vanilla CP/M-86 system.
Other S-100 systems like CompuPro and Cromemco and even NorthStar were all
versatile and well-built CP/M machines which could aspire to be called 'the
best CP/M machine ever.' In general I would even proclaim the category of
S-100 micros as the holder of that title.
Bob Stek
Saver of Lost Sols