25ms isn't horrible for gaming at all. In fact, it's fairly decent. I've played on a couple 25ms monitors and it's been fine. Sure you can notice some ghosting, but it's not going to ruin the experience at all.
I wouldn't worry about it. You bought the monitor, so just be happy with it and enjoy it. If you start using the monitor thinking it sucks, you really will think it sucks 🙂