Well, the Kumho's are in that category (ASX's or AST's) along with Avon Tech M550 or Fuzion Hri. all of these have better treadwear ratings than the Nexen's, and all will perform comparably (the Hri might be a little worse, but not much).
My point is not that the Nexen's perform that badly, its that for a tire thats a summer only tread pattern, they perform terribly and you might as well get a tire that will last longer and perform better in adverse weather. Sure, they are cheap, but they are cheap for a reason. Tire cost is a combination of initial cost and wear. Value is a combination of wear, cost, and performance. They don't do so well in my mind b/c of the wear/performance ratio. Cost/performance they are pretty solid. If you are just trying to get something to get you by for a bit until your financial situation gets right, then they might be the ticket for you (or the Sumitomo HTRZ might be as well; they are good on performance/price, BAD on wear/performance).