I bought this and returned it due to problems with the RM4.
It is a first run '02 RM4, and the modules are all '02 as well, except the Recto ('03). Sounds great, everything in excellent condition... except the RM4 would intermittently stop producing signal. It happened with different modules, and with different channels/bays. It would work fine for hours, and then.. no volume. Not slow volume drop, just.. fine, then nothing.
The final straw that led to me returning it was while recording, using the Recto in bay 4, it cut out. I stopped, switched channels, and the other three were fine. The Recto remained "dead" (LED still lit). I swapped a different module in, all good. Replaced with the Recto once again, worked fine.
I reseated all of the modules when I first got it, and tested the RM4 tubes. Just a heads up for whomever decides to buy it. I could have simply torn it apart and troubleshot the problem, but since it was an '02, the ~$50-100 boon of the package price was not worth it for me.