Using 15 Amp Power Cord in 20 Amp Receptacle

My Furman power conditioner started to hum, so I looked for a replacement. I got a good deal on a Shunyata Denali 6000/s power conditioner. The Denali comes with two 20 amp high current receptacles and four 15 amp receptacles.

I have five source components and one power amp. The power amp (BHK250) will go in one of the 20 amp receptacles. I had planned to connect my BHK pre amp, DirectSteam DAC, Innous Zenith MKII streamer, and Technics SL-1200G TT into the 15 amp receptacles. Where should I connect my Stellar phono pre?

I have a dedicated 20 amp line with a PS Audio wall receptacle. I’m only using the top receptacle, so that’s one place. Any harm in using the Denali’s remaining 20 receptacle?