Ive never ran 400. I've ran 350. It hurts but in my opinion not as bad as winstrol.
Winstrol actually hinders my training, strong test doesn't. Plus the BA isn't necessarily good for you either. Too much and I start running a fever.
25mg of prop is nothing. Doing 75 mg of prop wouldn't matter either.
If you really want to up the prop I would do a half CC of your 400 and a full CC of prop, twice a week. That's 600mg a week, plenty.