Simpson,

An analog voltmeter will, if anything, give you a more accurate reading of voltage on a PWM controller, as the analog meter movement will "filter" the response.

I would not expect to see any difference in "smoothness", unless the PWM frequency is very low.  Did you say you had a Minarik controller?  If so, I would expect it's probably using 120Hz, derived from rectifying the line frequency, as the PWM frequency.  A higher quality controller would likely use a higher frequency.  But there are also other factors, like I-R compensation, and the voltage and current feedback loops that can also affect smoothness.  I don't recall if any of these are adjustable on the Minarik or not.  A good PWM controller, well-matched to the motor, should be perfectly smooth, until you get down into very low RPMs, where the motor may start "cogging" due to commutation.  This is where BLDCs, excel.

Regards,
Ray L.

Thanks for all of the replies. I have the info I need now and a fairly good understanding of the various relationships I was asking about and everything makes sense.

Just a matter now of finding time to do the testing . . . .