Do you have to worry about the dye migrating over time, like to the body or other things it touches? I love the way it turned out and have a few ponies that could use a touch up!
I think it should be fine though I'm not sure what would happen long term... the last time I repinked was about 4 months ago and the dye has not stained any ponies.
The dye is also not lightfast- I left a bait g3 who's hair dyed with Persimmon in the window and it's faded nearly to white in less than 3 cloudy days, so I think if it does stain your pony it'd be quite easy to sunfade out.
You can also set the dye according to the Dr. Ph. Martin's
website so that should prevent the dye from bleeding as well (I haven't tried this yet).