Anything you do with a good system you will hear a change or difference now if you like it that is another story. I don't like spikes on my Sapphires M3s, I have a carpeted floor with 8lb pads underneath the carpet. I have more authority, details, and better dynamics and bass, with the spikes sounding much less real. So If I never tried the speaker without the spikes I would not have known what I was missing, the feet stay on the front but no spikes, my past speakers were the same, except for my Dynaudio Confidence 5 speakers where they sounded much better with the spikes. So you have to try things out and see how they work out for you. In fact, a great setup person who does audio shows is also against spiking speakers and feels that much more natural, realistic sound with more body to the music without them. So many use spikes and like them, some use them because they feel they must, manufacturers offer them because it is expected to have them for the past 20 years or more. I don't like spikes on my gear either, yes they clean things up I guess but to my ear no different than pushing upper highs and lower highs more forward much like turning up the trebble control on a preamp or receiver in the old day's the same effect.
I always have kept the grills on unless they designer said to take them off.
