Really funny thread for me, I have both and I never thought them to be similar in that way. Of course they are in the same colour family but on me at least they are quite different.
Prim & Proper is on me a lovely muted beigish pink where Madly is much more brown and almost bronze-ish but still pink. But definitely more brown and bronzey tones to madly than Prim&Proper which is more pinkish.
I love them both but if I should choose I would go for Prim & Proper. That's my favorite. I use it all the time.
In fact I have never swatched them side by side, I should do that, sounds like I will be surprised. maybe they're much closer than I think
