My Ti Team Pro has bag loops, my steel Team Pro doesn't. It's the wrong way round for weight weenies, isn't it? The Ti one is noticeably softer due to the more flexible frame (same dimensions as steel, about half the Young's modulus) and didn't really need breaking in. The steel one is like concrete and it took 1,000 miles before the first dimples appeared. I considered it to be fully moulded by about 2,000 miles, although some audaxers' saddles are completely swaybacked and they like them that way.
Urban legend has it that the black ones are the hardest.