Is this Casio cheating watch good for exams?

[ViceOfBTC21]

I'm thinking about buying legendary Casio Data Memory 350 cheating watch as easy and low-risk way to get good grades. Is it a good watch for cheating? Does your teacher had any suspicions? And, is it fast enough to use to protect yourself against teacher seeing your notes in emergency?

And please, don't tell me cheating is bad. I know it's worst way to get good grades, but nevertheless, you can't stop me.