I've got similar issues. My speakers came with somewhat blunt brass cones
that did not pierce my carpet. When I was making my custom maple bases, I
bought sharper spikes to try.
Well, the first problem I encountered was that my concrete floors are not
evenly surfaced (unlikely yours are as well.) Even a slight discrepancy in floor
level is going to create issues with unsteady speakers if you are using four
cones. I used nylon washers in various thicknesses to compensate. To be
honest, after all the tweaking, I didn't hear a bit of difference between the
two cones. My speakers weigh about 125 lbs. each, so they really compressed
the carpet/pad to the concrete underneath. I had also carefully plotted
speaker placement with test tones and a decibel meter. I think Audiavreseller
is right when they say it's not a cut and dried issue.
Another problem I encountered was that after fussing with the leveling
washers, the spikes didn't couple to the bases as well as the stock cones and
were prone to buzzing at specific frequencies at high volumes. In the end, I
took out the aftermarket sharp spikes and reverted to the stock cones. If I
had wanted to mess with reconfiguring four contact points to three, obviously
that would have solved the contact issue. But as I said, I didn't hear any
difference. Your mileage may vary. One things certain, I gained a new
appreciation for how much work a speaker manufacturer goes through in
developing every aspect of speaker's design!