[sdiy] Anybody worked with real Moog System 55 ?

[Jean-Pierre Desrochers]

Does anybody worked with real Moog System 55 ?

I'm building a VCO driver which will be very close
to the Moog system 55's  921A VCO driver design (parts & front panel).
I'm wondering about the stability of Allen Bradley pots used in such a design in late 60's.
I'm considering instead Vishay 249 series pots for FREQUENCY front adjustment
but they only are capable of 295deg mechanical rotation compared
to the original Allen Bradley's 320deg mechanical...
This would have an effect on the front panel FREQ divisions
(smaller span).
Since Allen Bradley doesn't exist anymore I'd use PEC pots
like this:
http://media.digikey.com/pdf/Data%20Sheets/Precision%20Electronic%20Components%20Ltd%20PDFs/MIL%20Style%20RV4.pdf?cshift_ck=1830796695cs506374199&client_id=5042
 
So my question is:
Were the original Allen Bradly pots that bad
about freq stability (carbon type) or this would still be
a 'fair' choice to me today ? 
JP