I am also fascinated by these early techniques. There is no question that is much more convenient to use a 3458a, but it seems like an awful lot of things have to go right for such an instrument to produce good answers. I read of the struggles in repair and calibration and cost, and I know the 3458 is not for me.
I real a lot of the earlier papers from the NBS and others, Frank Wenner, James Thomas, Edwin Northrup, and others, building on the work of Jimmy Maxwell and so on. It is interesting (to me) to see how they did so much with so little, and figured out many concepts that we still rely on (and often make oh-so-much-more complicated!).
Bridge techniques rely much more closely and simply on the fundamentals of physics. The behavior of current flow, and the reliance on a relatively simple and self-verifiable null detector. It's all the ratios. Direct or only-slightly-indirect comparison of a standard resistor against the unknown, where the measurement is determined by a variable resistor whose accuracy and characteristics are improved by a factor of 10,000 by putting it in the middle of a much larger fixed resistance, that sort of thing. Clever techniques based on the simple mechanisms available in the day. Measurements made at ppm's without any amplifiers. Without any amplifiers. Verifiable ratio techniques throughout, and somewhere... one (or more) calibrated standard resistor(s) to provide the absolute reference(s). Some (provable) Hamon buildups to scale the ratios up and down, verify linearity, and so on.
At last for resistance. I suppose there are similar techniques for voltage measurement, but I don't pursue that at this juncture.
My impression of modern test gear is that measurements pretty much always rely on internal resistors, anyway. They're inside there, and there is no normal hands-on with them; you may not think about them specifically, and just kinda trust that they're still right. It's way easier, and I don't discount that, but to my thinking, there are more assumptions involved. (And money!). You don't have to (but probably will anyway!) make a hobby of making/keeping it all working right. :-).
And you probably SHOULD have at least a couple of calibrated resistance standards around your lab, anyway, no? So it seems like it sorta comes down to letting your meter make a comparison with its internal standards, or having your standards out on your bench (or in the 925D, which is not necessarily required).
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It is 19.5 inches wide ((standard 19" rack), 20" tall (3sp + 3sp + 4sp) * 1.75 + filler strips), and 12.5" deep. I don't know what that is in metric inches, but I'm pretty sure it's still... big. It's liftable by one person, occasionally. I am putting mine a rolling wire-shelf cart that fits it pretty snugly, and then there's space for other gizmos on the shelves, and I can move it away when I'm not playing with it.
I think I would only get one if I (1) really cared about fundamentally-implemented resistance measurements, enough to invest more time and effort in, for example, building some good Hamon standards, and working on calibration, and (2) had the space, or could make the space, and (3) had the money thing.