My collection has a UK military Avometer 8 (with tropicalisation for use in the Colonies and extra metal case around the Bakelite, good for shielding and squaddie protection), and a Hartmann & Braun Elavi, but is missing a Simpson. I actually use them, mostly for current. Having a 5KV range of course is potentially (pun intended!) useful, even if it requires a very careful setup and hard thinking about Consequences.
Their limitations as to AC frequency and the loading of DUT inherent in a passive design makes one appreciate the more modern meters in the collection, like the 1968 Marconi VTVM and the 427A so much more ;-). Then, of course, if the passive volt meter says there are so and so many volts, we can be fairly certain we're not measuring ripple through a triac or a high-impedance sense circuit, but actual ommph that won't sag. That is a good indication in itself, especially if compared to what a more sensitive meter indicates.
As you say: the right tool for the right job.
Meters with mechanical movement have some properties that can be a no-go or limitation or can be a welcomed property:
You already gave the example of a limited input impedance for electromechanical voltmeters.
Another example are moving iron movements, those measure rms-values based on their principle of construction.
I do have some for measuring current despite having high resolution electronic ones like the HP/Agilent 34401, because quick changes are better visible; If you use them with external sensing (four-wire-mode on the supply side) you can get rid of their impedance mostly.
Of course, the active (FET or beyond) varieties give you a unique combination of capabilities - very good reading of changing signals combined with high input impedance. As far as ranges are concerned, the Unigor 6e/6eP is unsurpassed.
And when you look around some, you will find even values apart from the 10 or 1MOhm/V of the amplifier instruments and the ubiquitous 20kOhms/V of the most common types.
Take for example the 'Viererbande' (Gang of Fours) from Metrawatt:
The amplified 4E has 10MOhm/V for DC and 1MOhm/V for AC.
The Metravo 4H, which is the most universal one, comes with slightly above average 31.5kOhms/V.
The Metravo 4S, which is intended for power and electrical usage, has 1.33 kOhms/V, while the similar Unigor A41 has 3.33kOhm/V.
The Unigor A43 on the other hand, which was aimed at communication electronics, is a passive instrument
with 100kOhms/V (+ some capacitance measurement)
I have been scolded in the 'Show your multimeter' thread for my inclination to collect those late electronic analogues, but the real advantage lies in having the choice.
BTW, if one around here did never read that thread, you should look up my description of the Neuberger modular multimeter: that is one interesting piece (or rather a number of pieces) of equipment!
Its here:
https://www.eevblog.com/forum/chat/show-your-multimeter!/msg1201890/#msg1201890
When I was working with process control systems in a certain plant, we were experiencing much leakage and stray voltages so that even 20kOhm/V multimeters (and even some newer electrical testers) showed you a voltage where there wasn't one. I loved to use the ugly AN-USM223 there, because you could select from 20kOhm/V down to 4kOhm/V, it was unfazed by the corrosive and soiled environment and when you did not need it, you could sit on it.
I found it also quite useful to have both a passive and a amplifier version of mid-zero multimeters around. (they are both DC only and no resistance, so technically they are no true multimeters, but they are both derived from the respective Siemens multimeter series, so whatever).
On the other side, some variations of the DMM with pseudo-analogue displays have gone very far to make the observation of signal variations easier. While the Fluke87 was among the first to offer an improved resolution bargraph, it was not among those having the best solution:
Besides the Metrawatt M2036/2037, the Tektronix DMM250 (a rebranded Beha model, afaik) did stand out in this regard with its large arc-shaped pointer emulation ABOVE the numeric display.
But coming back to the Fluke87, the availability of two min/max capture modes with specified reaction times was also part of the solution, as one of the tpical applications where a pointer instrument was favoured was the measurement of peaking or inrush currents.
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