I decoupled my Vandy nine years ago and have never gone back to the spikes. I did place "unhappy" balls where the spikes would normally have screwed in and placed a 25# sack of lead shot (BB's) on top. A friend couldn't find the unhappy balls so he used hocky pucks and blue tacked them to the bottom of the sub.
Also, I have this all sitting on a sandwiched 18" cermic tile platform. I held the tiles together by using Mortite "roof and gutter" patch tape sandwiched between the tile's non-glazed back's. This also made the platform totally dead to vibration (knuckle rapped it). If you can't find the patch tape, you can use roof calking or rope calking. Other than the rope calking, this stuff is messy so be careful where you use it.
OBTW, since one of the glazed tiles faces down, it is very easy to push them around on a carpeted floor.
Good luck,
L
Also, I have this all sitting on a sandwiched 18" cermic tile platform. I held the tiles together by using Mortite "roof and gutter" patch tape sandwiched between the tile's non-glazed back's. This also made the platform totally dead to vibration (knuckle rapped it). If you can't find the patch tape, you can use roof calking or rope calking. Other than the rope calking, this stuff is messy so be careful where you use it.
OBTW, since one of the glazed tiles faces down, it is very easy to push them around on a carpeted floor.
Good luck,
L