I don't know if 478 has been used every year or not.
All of them have their advocates as to which was the favorite, or "best".
476 is the one most often referred to as the "best" of the three, but it's been out of service for years.
473 has often been referred to as the roughest of the three, dating back to days assigned to the Chili Line and then yeoman service after that.
I remember D&RGW employees liked the 478 because it pulled the best of the three. It used to have an odd thing about it, it would occasionally "miss" a beat in the exhaust. I've heard it myself, you wouldn't think such a thing possible, but it would occasionally miss a beat every now and then as it pounded up to Silverton every day with 11 cars in tow.