I think @ most live casino poker rooms, you're allowed to put in a request for a seat change. That is not the same thing as leaving the table or taking cash off the table. It simply means you are moving seats at the same table. The last time I was @ a casino, a player requested a seat change and that person was given a button to indicate he had done that. I assume that means there's only a certain number of times you can do it or maybe a limited time before you can do it again. Online I haven't seen an option to change seats.

Anyway, I wouldn't want to change seats until or unless there was an aggressive player to my left. I would be more apt to want to change if the aggressive player was also loose. As a second priority, I would prefer that players with large stack sizes be seated to my right so I have a positional advantage over them.