Are NAND backups interchangable between C1000, C3100 and C3200?
NANS size is identical on these models, all other hardware too, except for the internal Microdrive, AFAIK.
So actually is should be no major problem flashing a 3100 NAND on a 1000 and vice versa.
No problem at all expected between 3100 and 3200.
Except there are some mechanisms in the D+M menu which prohibit cross-flashing.