MOTM

I just finished 2 MOTM300 VCOs last night and spent some time playing 
around with the calibration.  I started at A440 using a very accurate 
frequency counter.  If I get the trimmer set exactly right for the 
octave interval between 440 and 880, the next octave which should be 
at 1760 is invariably a little flat at about 1758 with another octave 
up flatter still at around 3495 instead of 3520.  Going down from 440 
the octaves are very close.  If I adjust over several octaves I can 
get the 1760 and 3520 closer, but the 880 octave ends up a little 
sharp at about 882 and the 220 octave a little flat at 219 with 440 
right on.
This holds true for both oscillators, but one of them is a little 
worse on the high end than the other. 
I remember from my old Moog days that those oscillators tended to go 
off track as well in the upper range.  It seems to me that they had a 
trimmer for high end linearity which had limited effectiveness. 
Questions:
1. Am I being too picky?  
2. Should I just worry about the lower octaves and not worry too much 
about the 1760 and 3520, 7040 octaves?
3. Is it possible to improve the high end linearity by playing around 
with the value of R50 or is that asking for trouble?
Thanks to all for the help in advance.