Looking to buy a power conditioner


I'd like to add a power conditioner to my system. Prefer to buy used. Recommendations please. I have a dedicated power line for my system.
Thanks for you input.
larseand
I feel fortunate to have found a used pair of Shunyata Triton/Thyphons.
They transformed my system.
Retail was $18K. Got them for $4.5.
Anything Shunyata is superb. The most advanced technology.
They have a division that makes units for science and medical.
I'm on the Underwood Hifi mailing list. Seems like there might be some good ideas to start there...

https://www.underwoodhifi.com

They might have some slightly used units for sale.

I can see the wisdom in buying pre-owned hifi equipment. But, for some reason, I hesitate to purchase pre-owned power conditioning gear. Seems to me that if there was anything I'd want to have the full service life and protection of in new condition, it would be in power conditioning.

An exception to this might be if I knew the previous owner, who was upgrading because his equipment had outgrown his power conditioning gear. 

Perhaps I could be convinced to change my mind about this. 

Good Luck.
T.
I recently bought my first (used), an Isotek EVO Sirius. It has helped (e.g. seemingly lower noise floor), though the most obvious difference was in video. In fact, the difference was shocking!
I purchased a Furman it reference 15i brand new from an eBay store for a huge savings. Boyton-studio. Get a price from him and it'll be a lot less than anywhere else. I have no affiliation with him whatsoever. 
if you have a dedicated spur I’d go passive. I have very good results in SQ from an Acoustic Revive RTP-4 with their reference power cord