(Correct me if I am wrong) I believe it's one in every 4 grey horses develop melanomas.
I don't so much HATE grey horses, it's that if any of my mares were to breed, then I still have that huuuge chance of a grey. And I would really like to change it up! None of my friends can tell my mares apart (even though one is a rose grey, one is a dapple and one is a fleabit lol). And even during the summer, if you live in Oklahoma, your horse is NOT going to stay white:)