It’s not the image quality so much as the efficiency. You can create a 24 frame web video that’s 20% smaller than a 29.97 web video with the standard 3:2 pulldown included. Similar setup with the 24p DVD. Also a 24p DVD will play in native 24p on a progressive scan DVD player hooked up to a compatible plasma monitor or DLP projector. If you wanted to edit 24p standard at 23.98 it would require more effort in post to convert from 24p standard.
As an aside I think you can easily find a b-stock or used SDX at a pretty close price point to the Sony and you’ll be making a huge bump up in quality going from 4:1:1 25Mbit DVCAM to 4:2:2 50Mbit DVCPRO50.
Noah