i'm 23 and have crowding around a high right eye tooth(canine). Its not too severe but I'd like straight teeth and need braces to fix it. My dentist has offered me the latch style for 20 months for $4500. The price doesn't bother me but is 20 months a normal timeline? also, I understand he is a proffesional, but should I suggest another, faster option if available? if so what? thanks