The price. $400 USD. Spry can be easily be replaced by something like MooTools, jQuery, Scriptaculos, or Prototype all for free. That said, Spry appears to be free too. Though Spry's samples are all somewhat sluggish, as expected from the touted user friendliness. The browser compatibility check, for the CSS stuff too, can all be done online by a third party. Photoshop and Fireworks integration, whee. I see nothing worth the value. Worse, it's made by Adobe--well renowned for their resource hogging applications.

Those are my reasons, but I prefer to agree to disagree.

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Programmers are in a race with the Universe to create bigger and better idiot-proof programs, while the Universe is trying to create bigger and better idiots. So far the Universe is winning. - Rich Cook