Monster Regret!!

Chuck nailed it. Let your ears be the judge. If it sounds the same keep any surge protection for insurance.

Nordost QX4!!

Paul McGowan — founder and Prez of PS Audio — has a gazillion helpful videos on the Ask Paul section of their website.  A few of them answer your question.  Not surprisingly, their view is: use a P-15 or P-20, but if you can’t, go directly to the wall.  Older power conditioners or glorified surge protectors may help things sound "cleaner," but they also usually mute dynamics, imaging, air, depth, and decay because they ruin the low-impedance-output-to-high impedance-input relationship you want as the signal moves along it’s path.   I’ve owned the BHK pre and monoblocks; fantastic gear.  They definitely sound better plugged into a P-15, which I still use for my Audio Research gear, preferring it to the Denali 6000T.  (And, BTW, the BHK pre sounds markedly better with the Tungsram input stage tubes that Upscale Audio promotes for that pre.)  No affiliation between PS Audio and me, but I’m a huge fan of the P-15.  

Nothing wrong with monster. I’ll bet we all used some of their products at some point when we got started in this hobby. They were the pioneers. It’s what sounds good to you that counts. Me, I’ve been impressed with shunyata conditioners. Even my wife can tell the difference. Do whats best for you and have fun. It’s a great hobby. 

My thanks to you all!  Great advice!  I knew the community would know.  Thanks again!