The main difference between this setup and a RIMS is that they don't mill the malt when they allow the grain to be circulated. The cavitation pulverises the malt. This is actually a massive benefit because dry milling malt is a major cause of infection in a brewery.
The other benefit is that they are able to mash at a much lower temperature and still get decent extraction. Even down to 48C (118F) allows them to get 91% efficiency in one case. This is on par with RIMS (most reports I've heard is that people can manage mid 90s efficiency), but of course rims has to maintain a temperature of about 65C (150F).
Side note: Their reported temperatures for mashing without recirculating the grains is a bit crazy -- in the mid 70's C -- all much over 160F. They are going to be deactivating enzymes at those temps and that probably accounts for their decreased efficiency. I really can't understand what they were thinking.
There is some mention of protein make up, but my main worry about mashing at such a low temperature is the break down of larger proteins. They have a picture of frothy beer with a caption about foam stability, but the proof of the pudding is in the eating. Also, that picture shows a very hazy beer.
The other thing they talk about is isomerising the hops without boiling. That's pretty cool and would definitely reduce power usage. But again... that picture of nearly opaque beer haunts me.
Finally they talk about cavitating the fermenting beer in order to remove CO2. That seems reasonable, but I would worry somewhat about how the yeast drops in that condition.
To be honest, I wish they had stuck to mashing in this paper. It's strange to see a paper cram as much as this one does in one place. Normally you want to stretch it out over as many publications as possible ;-)
The last thing I'm curious about is how they produce the cavitation. I really couldn't understand their description at all. Is it just a matter of the design of chamber in which they pump the wort? That would be extremely cool, but I'd like to see a better description. A mash system that depends only on pumps would be ridiculously nice to have.