But what about comparing different ways of obtaining the same
inductance to find those with higher or lower Q?

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To double Q, whatever it is, just double length and diameter of the
coil, wind on a number of turns of much thicker wire for the same
inductance, and Bingo, Q is doubled. The value of Q is unecessary.

Efficiency and bandwidth can be deduced by calculating from the known
values of wire and radiation resistances. But I suppose Q, once
available, would be a short cut to crudely estimating bandwidth.
Additional information is needed.

The loss in the coil may not be the dominating factor. What matters is
the System Q. It can be considerably worse than coil Q.
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Reg.