Thanks to all who responded. I found that vibration of KLF-30s was barely detectable and no more whether with or without the KSW-15s under them. No matter what level is fed to the KSW-15, the KLF-30s stay put -- I had expected them to walk off the subs.
I may add a small rubber furniture pad under each foot sometime in the future to prevent someone (like my grandson) from accidently moving their position.
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KLF-30 fronts
KLF-30 rear corners
KLF-C7 center
KSP-S6 sides
KSP-S6 rears
KSW-15 (2) rear corners
HPS-1000 front sub
Denon AVR-4800
Marantz 10B tuner
Monster HTS-5000