Fahim, since I had no success with the
Skywatcher pier I recommended to you above I bought and tried casters from
scoperoller.com. To be honest I didn't expect them to be so good.
I tried casters from Bunnings and I could not see any way why my mount would be completly steady and not shaking when any kind of casters attached to tripod legs.
However after I tried casters from scoperoller I can confirm that this is a real low cost portable pier solution. They sell tree types of casters for different types of mounts and I believe that they also have casters for G-11.
I've bought a zero motion version of casters for my EQ6 Pro and they come with locks that actually block both a wheel and a caster base rotation. So when all three casters are locked I cannot see any the difference in stability comparing it to tripod legs that have no casters at all.
In terms of mobility the casters make it very easy to move your mount around. I can easily move my whole 50kgs setup with just one hand.