Maybe we should clarify something, a voltage stabilizer wont do you any good. That is the gizmo where you plug electrical apliances etc to prevent fluctuations in voltage, now a cold head stabilizer is inavaluable, the zone VI timer/stabilizer also has a "beeper" or metronome, I can tell just by the lenght of the beeps that sometimes the exposure is longer due to cold tubes, as they warm up the exposures get shorter. So sometimes a second is about 2 seconds, and when hot is about 1/2 second.

So if we are talking about a cold head stabilizer to adjust the printing time it is definitly worth it, a run of the mill voltage stabilizer is of no use, as the tubes will still be either hot or cold and you wont have a way to measure the light output.