My power seems clean with the EP-2050. I cannot say I had an "A-Ha!" moment after it was installed, but I'm comfortable knowing there's real science and engineering behind the product, and that it's protecting and filtering the power throughout my home.
Another user utilizes the EP-2450 Home Theater unit in addition to the EP-2050 and likes the results. I remember being told by Doug Joseph at Environmental Potentials that this was the next step if I wanted additional filtration at the system level.
I presently use an Alan Maher Reference Power Center V2 with the components, but frankly I do it more because the RPC V2 has eight outlets that I find useful. I could easily live without the additional filter unit.