I have had both my Lambda magdynos converted to electronic regulation. I could not face the festering 1920s internals. The new regulator fits inside the existing space in the unit, and has provided a carefree solution.
It takes a bit of an attitude change, as the new scenario looks at battery voltage and its requirements, rather than "balancing the discharge", so there's rarely much variation shown on the ammeter, except a short boost after using the starter motor. For total logic one should probably fit a voltage meter rather than an ammeter, but that was a step too far for me.
My auto electrician friends (I am not an electrical expert) tell me that modern batteries, designed for alternator systems, have the ability to burn out a dynamo by consistently requesting maximum charge. Electronic conversion changes the demand to what is actually needed at any one time, if you have a large capacity battery that will mean a less demanding life for the dynamo.