That would take too long to grind enough money to use a skill that is not guaranteed to pop up, and since it does NOT count as an overkill you would get 1 stat sphere at a time. It would take ages, and alot of money. I just level grinded until I got 3+ chars to get everything on the sphere grid(Doesn't take as long as you would think in Omega or Sin) and then I got thier best weapons and some BHL armor, and I killed all the arena monsters.