Best AC line conditioning devices?

Name your fave and any comparisons done. I'm particularly keen on this as I've experienced some great results (and some flubs) but I can't audition all. I admit to being extreme for isolation/conditioning for digital.
I have not used any Sound Application devices. I might add that I loaned my unit to a retail dealer for YG Acoustics...he bought one .....says a lot to me. They are only available factory direct. He trusts his ears, he has very good ears, and heard what I did as well. His room at the Bay Area Audio Show never fails to impress. A picture is up at either his website for Loggie Audio or at VH Audio. I can't recall which one.
Apparently the tube used is a Thyratron tube and affects the phase angle. An EE may want to chime in and contribute more as I am not an EE. All I can say is that when in a system, computer based, cd, vinyl, especially systems with non tube power supplies, the results are very positive. With tube power supplies, I note less of a difference.
Sabai, any chance the show was using balanced power? Why were all in the room unimpressed?
sorry for the late reply...I am too busy listening to music! I use the HB Cable acrylic power slave and also the power dragon alternating with Yamamura power cord as I have all my cables from Yamamura, so I give a bit of preference to the sound of all yamamura ssytem cabling...

I don't know if the system was balanced. Why was everyone unimpressed? Because the unit did not do anything special for SQ.
Understood Sabai. (However if the ac is perfect no unit will make any difference. I think a real evaluation can only be made where the ac is needing conditioning. I think 'comparisons with other conditioners' are needed for evaluation.) I asked if the power was balanced because the SOUND APPLICATION is designed for normal unbalanced power with a normal ground--it won't work after a balanced unit. However it is effective if placed "before" the balanced unit. Most people would not be aware of this.