I was not a RS user at the time and it's quite
possible that the rumors I heard
regarding the M1 and those about the M3 were geting mixed together. I wasn't
even aware that there wasn't a two-sided option on the stock model 3.
The third-party controllers were most popular on the Model 1, since the stock
FDC was SD. There were a few third-party controllers for the Model III and
the early Model 4, but they weren't as popular as the 1793 was more capable.
The stock Model 1 FDC also had reliability problems that lead to third-party
data separator plug-in circuits.
The only Model 1/III/4 that came stock with DS drives was the 4D. Any other
DS setup was third-party. The stock III/4 controllers (both the add-on in
the III and early 4 and the built-in on the gate-array 4) had no problems
with DS drives.
--
Eric Dittman
dittman(a)dittman.net
Check out the DEC Enthusiasts Club at
http://www.dittman.net/