I own a music store in Southern California (Kaye's Music Scene). I've been disappointed for years with Casio's drum kits. They've always sounded terrible up until the new AiX sound engine came out this year. Finally, the sounds on these new models are great, especially at these prices. Casio had done a great job with Privia products featuring really good pianos, electric pianos and organs but all there other products still had poor quality drums, not very good sounding guitars, basses, horns, etc. Whether you like their user interface compared to other brands, you will be impressed with the new sounds, effects and editing capabilities. Comparing these models to older products, all I can say is go and find one and listen to them!