It's a regulated power supply and should do what is says and provide a stable DC source to whatever relevant circuit needs to be powered. You would see the same noise improvement by using pretty much any standard regulated power supply, modern IC regulators do a good job at providing clean DC.
What Justin has done is shown that the Bozak's discrete circuit design doesn't reject supply noise very well which is going to mask the music that can be heard.
The UREI improvement is not as great as the Bozak as the TL072 op-amp has superior power supply rejection than the discrete design of the Bozak.
You may want to ask Justin to supply what the noise benefits are going through a line in on the UREI instead of the Phono section especially if you’re a heavy digital user.
A good regulated supply is certainly a worthwhile improvement if you like hearing music instead of noise.