It'll ease pressure on heavily MAD classes (those that rely on several stats being high) a bit, but will otherwise be nearly imperceptible. People sometimes talk about five-point differences in point buy as though they're the difference between scratching in the dirt for roots to eat and leaping from dragonback to dragonback, stabbing dragons in the head as you go, but really they're just a few +1's here and there. It's pretty easy to see, if you build some 20-point characters and then shuffle stats around to convert them to 25-point characters, that it rarely makes a striking difference. If you're trying to compensate for a low-magic setting than it probably doesn't hurt to go to 25, but it certainly shouldn't cause any problems.