guiding relays vs scope controls

I seem to have problems with the autoguiding relays of my sbig camera.
Haven't really objectivated the issue but it shows up with two different
mounts using two different cables, so I guess there not much room for
doubt.

I have therefore switched my guiding from guider relays to telescope
control. Is the performance going to be markedly different? So far,
everything is fine, but I am using a very short focal length (540mm) and
have had to cut the aggressivness in half, all other things being equal.

Pierre
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