Eric wrote about the AT&T Unix PC (7300):
  Biggest problem was how slow it was at floating
 point, probably due to a crappy math library. 
Was it significantly slower than other contemporary 68K machines
that used software floating point?
  I don't even think there was an option for a
68881. 
It would have been quite surprising if there had been one, since the
MC68881 wasn't announced until well after the 7300 was introduced.
Eric