i thought of something; a magus running around with a cold iron weapon adding +2 equivalencies at level 5. level 5 pc wealth should be about 10k, yet buying a +2 cold iron weapon starts at 16k
i didn't take the time to look at the numbers at every time the bonus goes up, but at 17th bumping up a masterwork cold iron weapon to +5 is comparable to a drop in the bucket, but bumping an already +5 do a +10 equivalency equals 3/4ths character wealth for that level.
It's not that big of a benefit. Fighter Weapon Training and Weapon Focus/Specialization feats keep up for the most part. Favored Enemies, when picked intelligently offer a similarly good benefit. Additionally, those abilities work within an Antimagic Field. Smite is probably better than the Magus enhancements, though it is suppressed inside the Field.