The only difference I've found is that there is a smaller selection of 25mm tires both at my LBS and many of the online stores, so when they put tires on sale, typically you won't find 25s.
From a ride perspective, I switched to try to remove some road buzz. At the time I also switched from a 20 spoke ritchey deep section to a 32 spoke mavic OP so I'm not sure how much of the added comfort is due to the tire versus the wheel.
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2014 Specialized Roubaix2003 Interloc Impala2007 ParkPre Image C6 (RIP)