Heavy difficult to move speakers- how do you deal?

I have never seen 520 pound speakers. That’s nearly 3 tons of speakers

The sliders will work but you will have to get the discs under the spikes before setting them on the sliders which is a PITA.

Alternative idea to move them only once for placement purposes:  get a piece of Masonite that is a few inches larger than the footprint of the spikes of the G5s and put the glossy side down.  Slide around until you've dialed the position, mark the spot then remove the Masonite.  Pro tip from a former mover:  Cut the Masonite in half, duct tape the two halves back together on the rough side, this will be the side facing up under the speaker.  Slide around all you want then when set, peel off the duct tape, tip the speaker to remove one half of the Masonite, tip the speaker the other direction remove second piece of Masonite and Done! 

If you don’t use the $7500 quantum tech sliders by QSA, your soundstage will never be right. Something about the way they slide aligns the speakers’ molecules. The difference in sound is not subtle. When your wife runs in from the kitchen to ask if you bought a whole new system, just please make sure the quantum sliders aren’t on the floor. She’ll slide right out the window. 

Someone needs to go back to school. One ton is two thousand pounds.