and unquestionably will be best served with an ultra sonic RCM.
I seek the best sound quality, and I stopped using my ultra-sonc machine, because I heard no improvement over my traditional, vacuum RCM.
If there was some strain-to-hear-it improvement, it was not worth the time, noise, and effort of the ultra-sonic machine.
I have a revealing system, and seek out white hot pressings. Yet, to my ear, my ultra-sonic machine provided no sonic improvement over my traditional VPI machine.
Also, ultra-sonic machines are not too good at cleaning heavily soiled pressings. They are good for the clean-up crew (in a manner of speaking). They do the detailed touch-up work. Whereas, a traditional RCM will quickly whisk away clumps of filth.
and one year in of moderate use my machine now needs a new water pump and solenoid valve.
My ultra-sonic needed repairs just shy of the warranty end date. And I had to ship it to Germany (not a single authorized repair shop in the USA). Argh!
My ultra-sonic machine needs distilled water, which evaporates. So if I only need to clean a few records, then I have to fill the tank with distilled water. And due to my infrequent use, the water evaporates by the next time I want to clean any records.
I got tired of that, and stopped using my ultra-sonic machine years ago. My VPI 16.5 machine does a great job. As good as a current model? Maybe not? But how much better can it be? I use record cleaning fluid and a brush, wipe off the record, and the vacuum dries it off and picks up any dust that the brush might have missed.
Finding a better sounding pressing will do more for sound quality than any RCM. But when you land a better sounding pressing, you are back at square one, where you want it to sound as good as possible. For me, my VPI 16.5 machine gets me there (or 99.9% of the way there).

