I think any mage or mana heavy character without resist is a fail. It works.. i guess, but even mosters mana drain and mana vamp. If you have a weapon skill or alchemy or some form of non mana offense then it would be ok to me. But when you need mana to survive, do damage, cast utility spells, etc I think it's a dumb idea to go without resist spell.
I play low meditation characters tho.. perhaps thats why I feel this way.