Antec sent me a sample of their new Proto to review. Same as Sonata III, but without PSU. I think $49.99 would be easier to digest. Unless a locking bay door and HD trays are your main criteria, I would point people in the direction of the Antec 300 for $20 less or the Cooler Master 690 II Advanced for $79.99
I've posted more photos and a short review on my blog
Antec Sonata Proto Mid Tower Case Review. | Case Mod Blog 