If you've been happy with the 25s why not stay with them? Reducing the pressure in each tire by 5 lbs will make a noticeable difference in comfort.
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A conclusion is the place where you got tired of thinking. - S. Wright
Favorite rides in the stable: Indy Fab CJ Ti - Colnago MXL - S-Works Roubaix - Habanero Team Issue - Jamis Eclipse carbon/831