Power Conditioners Recommendations

Looking for some recommendations.
In your opinion / experience what would you say is a good deal / good value power conditioner for about $250 used?

I am looking at Adcom ACE-515 as the ceapest at about $70, Monster Power HTS 36000Mk2 for about $160 up to Furman PF Pro at $250.
Anything else?
I have a tube amp and CD player for a source

thanks!!