The benefit of switching hands is you gain a little bit of angle while spraying or shooting through an opening, if done right. The width of the gun positions is enough to make a difference sometimes. Here is my alias for it, it's in my config.cfg.
alias change0 "hand 1;bind x change1"
alias change1 "hand 3;bind x change2"
alias change2 "hand 2;bind x change0"
Of course you have to bind x to change0 or such before you can use it. Being a sprayer/liner/camper/very *friendly* person I use it quite a bit.