Another tip for you if using casters with swivel locks...
I stumbled upon this one purely by accident. If the casters can lock every 90 degrees, lock them at right angles as shown in this picture and the bench will not be able to move. It eliminates the need for wheel brakes or floor locks (like what I installed beforehand and never use now - wish I would have made the discovery it just a bit earlier

).
In my case, I lock the swivel caster at 90 degrees to the rigid casters in the back when I'm working on the bench in the middle of the room. When it's time to roll it back in its cubby, the swivel casters get locked inline with rigids to force it to roll straight in to the wall and pull back out easily.