Wow! It's so much more comfortable to hold than the iPad 4. The difference in weight and density makes it such a pleasure to use. The speed differences I think are minor, between the air and 4. I think the iPad 4 -> iPad air is a much bigger upgrade than iPhone 5 -> iPhone 5s. If your using your iPad allot you will appreciate the size and weight differences. Functionality wise everything you can do on the air you can do on the 4. It just that design and weight matter for iPad versus laptop per say. Btw the air def doesn't feel cheap. I recommend to upgrade if you use your iPad allot. If your money constrained like me you can probably hold off. I really want to keep the air, but let see what I can do to convince my wife .