You have to play one to the fullest to appreciate the nuance and subtilities to manage a high DPS score. The difference in playstyle from the other caster classes is also very notable.
For fun, I played a friend's low 40s wizard recently, and marveled at the ungodly amounts of damage each of the spells did. Yet, I discovered a wizard really didn't have the same casting methods a Conjuror has to prevent aggro-stealing. A crit at the wrong time on a big nuke, and no more finger-wiggling bathrobe-wearing halfling.