I can see that the main use for the E-choke is not to replace a choke but to obtain the silencing benefits of one.
I will say that there are applications where the choke offers benefits of voltage regulation and improved efficiency of the power supply as well as better power factor. Rectifier peak currents are much less a concern when a stout choke is used.
Very high power >1KVA amplifiers I always use a choke input, and sometimes to reduce transients accompanying class AB operations, will use a resonant choke such as 2H in parallel with 0.88uF is used, before the capacitive filter.
I prefer the nasty old chokes because the voltage regulation is much better than a capacitor only. This is not very important for class A amps, or even for those that enter AB only near their limits with max/mincurrent variation of <1.5:1, but is very important when the current varies widely as amp designs approach class B end of things, varying more like 2:1 to 4:1.
I am running a 4800V 2A supply, choke input followed by a 31uF oil capacitor. At this time in a 6KW class AB amplifier under construction. The power supply is complete and tested. What I can say is that with either the 30H choke or the 2H/0.88uF resonant choke setup, the ripple is 1-2% and regulation about 1%, that is fantastic. On step loads such as 300mA-2000mA, which is what you might get in an AB amp especially for RF, or for bursts of sound (1812 overture cannon anyone?), the resonant choke is a must. The type of amp matters less than the profile of the load on the power supply.
About amps - note the 6L6 and EL34 conditions, since it's common:
push pull class A:
120-140mA current ratio 1:1.16
134-155mA current ratio 1:1.16
push pull class AB1:
88-132mA current ratio 1:1.5
88-140mA current ratio 1:1.6
116-210mA current ratio 1:1.8
push pull class AB2:
78-142mA current ratio 1:1.8
88-205mA current ratio 1:2.3
push pull class "B":
50-182mA current ratio 1:3.6
I believe it would be fine to use Mr. Vanderveen's electronic choke within its ratings in any amp that has already a choke, and that similarly pleasant improvements will be made. I think it ought go after the choke in those cases but someone who knows more about it should comment.