The Rada is a SUT with tube gain.
I have the upgraded resistors and phase, mono, rumble. It was fun to flip the switches for a while. I never touch them now. If you have rumble, address the feedback in your stand. Phase?? Well, maybe. It hasn't affected any of my records yet. Mono. I guess technically it makes a signal more coreect. But with a mono record its not a lot different. The record is already mono.
Thats just my thoughts. I guess Im saying, on a budget, the additional features are small gains for the money. The basic foundation of the unit is very high dollar gain. I'm very happy with it. B