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 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
I bought 2 of the new Audience Forte power strips with the free Forte power cord (the CableCo web site has this deal. One of these strips is extra inputs for my filled up Torus RM15. The other one is for the family room gear. I am not sure if this thing helped the audio but on the video side both TV I have hooked up to it have a much better picture.

I trust Audience gear and just bought it without much research. Very happy with the purchase.

Audience Forte V8 Power Conditioner (thecableco.com)

There’s a nice Audience aR2-TSO available here at half price, and at a lower price point on US AudioMart there’s a Running Springs Audio Duke that’s below half price.  Both only offer two outlets, but you can easily add a good power strip to expand outlets if needed.  Best of luck.