If you're talking about doorways, what I've found works relatively well is to turn the cab sideways then tilt it towards you so the side of the cab is leaning on your thigh, then grab the handle on the far side of the cab, pull, and balance it on your thigh while hobbling through the door. Works with my carvin legacy 4x12 loaded with two EVM's (so basically four regular speakers).
Caster-wise, they get kinda annoying as they catch on stuff, hit things, make cabs harder to fit in cars, etc. If the cab has good handles on it I don't really mind carrying it, and if the ground is flat I just throw it on my skateboard and ride it over anyway.