Understanding phono stages/What to look for?

I have been using the BC on one of my systems for four years now. I am considering only the optional power source. I like the easy settings, and the sound is great. On my high-end system (read: high-for-me), the Linn has one for twice as much that is made for it and tucks nicely inside. And, similar to yours, my BC is being used with a 35 watt tube integrated. So I doubt you would want to consider anything else unless...
But the huge difference comes from the relatively new need for them in a, thank God, growing market for fifteen unbroken years. I have heard great stuff from the outboard CJ, but I feel no lack in the Linn. If I had another table in my best set, I would seriously consider it.

The OM20 cartridge you are using is not really suitable for the Rega arm.The Dynavector will be a much better match and then you will begin to hear what your turntable can do.The phono stage you have is very good but obviously the more money you put into something like a phono stage the better it should get.As it stands I think you will like what you hear.Look through the archives here and you will glean much info on phono stages and matching different components.

The PWX power supply will transform your cubes into monsters for a very resonable price. I and a friend each had BCs with the power supply upgrade with great success (I also used a Dyna cart- you'll like that too). You have to spend A LOT MORE $$ to get appreciable gains over the Black Cube with the PWX power supply