I advocate wheels for heavy speakers, slip surfaces for medium sized (sized so speaker doesn't move, but moves with effort).
to help find best and then alternate locations and alternate toe-in
my optional positioning, comments
3 wheels/slip sheets, so it's more weight per wheel, and 3 always finds solidity, avoiding shims.
casters: dual wheel furniture grade have less wobble in their axels than high quality single wheel.
surface mounted versions of wheels is easy to find.
Avoid Tip Over When Moving: flat bottom, no skirt, 2 wheels front, 1 wheel rear, and two anti-tip corner blocks rear, just above, not touching the floor normally, hit the floor if speaker begins to tip.
a good time to consider tilting the speakers back, aim tweeter up to seated ear height, and alter angle of initial reflections off floor and ceiling
mine, lying on their face, the skirt is the anti-tip solution, front block tilts the speaker back.
btw, I'm 75, have used spikes, other methods, they are no better in my experience, and limit movement needlessly, restrictively.