I'm from the UK so the steering wheel 'belongs' on the right hand side. However, I've driven thousands of miles across Europe and Canada.
The only time I ever struggled with driving on the other side (other than the occasional lapse while doing a U-turn on a very quiet street) was driving over the Alps in a manual hire car, driving a very narrow road with hundreds of switch-backs, where my weak hand (I'm right handed) wasn't used to the task of steering.
I can't say I've ever noticed any difference in vision.
The only time I ever struggled with driving on the other side (other than the occasional lapse while doing a U-turn on a very quiet street) was driving over the Alps in a manual hire car, driving a very narrow road with hundreds of switch-backs, where my weak hand (I'm right handed) wasn't used to the task of steering.
I can't say I've ever noticed any difference in vision.