Thought I'd add to the discussion as I just took delivery of a Tesla PowerCell 10 line conditioner and the break-in seems to be very similar to the cables... especially the power cords. Since it uses a quasi active field to condition the a/c it uses a MPC as well (with a much more flexible cable coupled with a slightly different connector). In addition it is Quantum Tunneled with a cable they call "the octopus" (all 10 outlets tunneled at the same time).
Sound-wise the PowerCell seems to be going through the same phasey ups and downs as the cables, but not unlistenable. Already the background is amazingly more quiet than ever before, allowing much more detail to come forth. It's interesting in that resolution is taken up a few more notches because the soundfield is so much quieter, NOT because voices and instruments are more sharply delineated. This seems to be one of the trademarks of the Tesla line in general in that it allows the aspects of ones gear that are positive to shine through even better. If you have a tube amp or hybrid, those qualities that led you to that particular amp are more fully realized with Tesla cables and now the PowerCell.
The PowerCell is an absolute no brainer. I would say to if one was wondering where to start with the Tesla line, then a T3 combined with a PowerCell 10 or 6 is where you should start. I believe SR is offering a packaged deal with a 5ft. T3.
I'll probably be running an extension cord off the fridge for a couple weeks to speed up the break-in.