A masterwork weapon has something like 4-5 extra damage. That's a lot, typically equal to another level of powerstrike or so, even more on some weapons.
Let's not mention how a few points of speed mean a lot.
If it's a overpowering advantage, then everyone will grind to get it, because they'll need one to compete - which would suck. If it's a nice advantage to have (like now), but is not blatantly OP, then it's a choice you make, or don't make.