Spikes or Spikeless

Wow - Someone put a lid on this open can of worms...=)
Thank you for all your input - I will give a few ideas a try: Im thinking try the Spikes to the concrete and see if that works. At 50# each I just did not think the spikes would "penetrate" into the concrete and perform properly. The idea of the spikes is to hold the speaker stationary. I was afraid they would "slide/vibrate" around. I will update on how much a PITA it is or was not...and my conclusions

Ended up using the extremely sharp spikes on the front 2 post of each speaker. While using a not so sharp on the 2 rear post.
The front drilled through to the concrete and the other 2 rear ended up not going so far....
Got them all balanced and they decoupled the speaker from the floor and prevented unwanted damping.
Really sweet sound.
Thanks for all the adavise....