You are being offered the strength and constitution of an ox, but as a side effect you're also going to grow to be a big big lad, lass or other, with a big honking pair of horns atop your head, and become a pure herbivore. Would you?
@TheBreadmonkey I'm sure you'd make a lovely Minotaur (Benotaur? Beigetaur? anyway) and you'd have a lovely time being one! Imagine the satisfaction of stomping around the place, being able to reach everything.