I am on my way to becoming ambidextrous, I'm a leftie but I'm slowly learning to write with my right hand. It's tough but I think it will be very useful later on.
It really does get useful especially if you hurt your writing hand or are in a position where trying to use your writing hand could be dangerous (up a ladder for instance) I've always been vaguely ambidextrous although I'm still mostly right handed for strength, a good exercise I've found useful is to get a small ball of other object and throw it back and forth between your dominant and secondary hands it will help build the coordination and strength up in your secondary hand.
For non-ambidextrous people trying to write or manipulate things with the non-dominant hand is like trusting a clown with a pie during a performance, or a drunk person to drive, something is going to get messed up.
You know what I mean, so dont say it XD
If you were me you would "pretty good" yourself every day