Discs don’t provide any benefit in a criterium. As msu2001la said, if you’re having to brake hard into a corner, you’re doing it wrong. I actually open up my front caliper for crits because I want less front braking—I don’t want to accidentally lock up my front wheel if I panic grab my brakes. That’s a sure way to take yourself and everyone around you down.
Plus, you’ll make your front end heavier, possibly affecting handling. You’ll have to get a new front wheel and left lever too. This doesn’t seem to offer any benefit.