There's nothing wrong with a little healthy competition. But if you're going to challenge someone to compete with you, just make sure you do a little research in to who you're dealing with. No one wants to get their butt seriously kicked by a master.
1.) From sarahohimesama:
Some Japanese client that studied in France asked me for a translation job but wanted to change all my sentences to prove she was better than me at my own mother tongue. She ended up writing something grammatically correct but that sounded so horribly sexual that if you tried and googled the terms you would only find porn and erotic novels. I had to tell my boss she was forcing me to write porn (because it was for a mascara brand that was supposed to be sold in France) so he could stop her and after that she stopped trying to best me.