I was in the market for some garage cabinets, for the price of anything new the extra money is well spend on the Gladiator/Craftsman or Kobalt brands.
I priced out some cheaper wood cabinets as well, add the cost to beef them up to hold paint/ parts/ etc and it wasn't worth the trouble.
I looked on Craigslist but everyone things their stuff is gold. Not much money to be saved and it was hard to find a matching set.
Have you looked into constructing your own with 2x4s (or 4x4s) and plywood? It would be the cheapest route and one of the sturdiest as well.