As always it is system dependent. I went to look at your system and noticed it gone.
I have used amp stands for decades. I have high quality amps, tubed now. Originally I remember a small improvement. It is likely adding 100 lbs of amp stand will help, just from the mass.
I recently put springs under mine (on the amp stand under the amp) and definitely noticed an improvement.
I have been toying with this idea while talking with an Audiogon member that whether cones (spike like) or springs are more effective might be that coupling with a suspended floor (which may already have absorbed micro vibrations) is better and springs are better when on a cement ground floor (since direct coupling with the ground will pick up micro vibrations) work better. He found cones worked better on his suspended floor and springs worked better for me on my concrete ground floor.
I’m planning on buying a seismometer in the next year or so, so perhaps I would be able to experimentally substantiate (a little bit) the idea.
Anyway, the amp stand with spikes or cones under on a suspended floor might be the best. And the amp stand with springs or anti vibration devices on concrete might be the ticket.