Well, if you intend to re-use the calibration, you definitely should do that one calibration for declination close to zero (celestial equator) and near the meridian (max. altitude).   The guider then automatically scales the result to whatever location you are pointing at.  This has always worked perfectly for me, both with PHD2 and now with the internal guider.
Calibrating at high declination (north or south) is suboptimal anyhow, because the RA movement of the star is reduced by a factor cos(DEC).  This can easily make the guide star movement drown in noise, unless you use long (and many?) steps....
 

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