It's fine. I've got one bike with a 30mm front rim and 25mm rear, with 2.5 WT DHFs on both ends and the profiles aren't that different.Has anyone run Maxxis WT 2.5s on a 25mm rim? Is the tire over round and harder to reach the side knobs or is it fine?
The rear does have cushcore in it, which I think does square the tire off slightly by pushing the sidewalls out, for what that's worth.