The best mid priced Grado In your opinion?

I am considering a Grado mostly because I can audition them but haven't got a good starting reference . Amongst their full line of products which mid level priced product less than $700, I'll say arbitrarily, is the best and why? It can be a very inexpensive one that is simply better and a giant killer, such a suggestion is more than welcome, I don't grade a product based on it's price, don't be afraid to voice your opinion. Thanks