Quote Originally Posted by t0r012 View Post
full umd ranks access + bonus skill points + evasion on a low HP class + synergy with the prime important trap stat Int.
trap skills are just icing

all of that for a measly -1 DC ( -1 levels & -2 Int capstone)

me personally I'll take a WF 18wiz/2 rogue swiss army knife over cap wiz. Been meaning to roll one , just havent yet due to monk addiction with a pally chaser.
Fixed that for you (in red and black)... there's no loss additional loss to DCs due to being 18 wizard (or 17 for that matter).

Spell Penetration is what's affected by the loss of casting levels.