I was thinking about just building my own of these but this is probably cheaper than I could do it ordering the parts. And probably better.
Every unit gets its own tap on the toroid, which is big enough I think the 500mA rating is conservative. That’s good attention to detail as it will be the quietest arrangement. External power supplies are how the original Neves worked remember, it’s quieter external as well. There are zero criticisms of this unit although it could be shorter…the dimensions are made to match the “Jr” line as 1/4 rack.