It depends. My personal preference is the large Multipocket, but it's more of a casual everyday bag. If you are looking for something that can be used when dressing up I would chose the Julianne. Good luck with your decision!
The MP slouches, but it shouldn't crease. The lrge also has protective feet on bottom,and can keep unzipped while juggling baby! -- I was always grateful for easy access & durable when my babies were young!!
Of the two bags looking at, I think MP is a great all around bag. Mine is 2004 and still going strong --- no creases, slight wear on piping and a few spill accidents! - But Black can be retouched if that happens.
LARGE MP . The soft calf leather will get a little softer over time but its an even change. I think the bag is even better when it softens. I have two of these in ivory and black and neither have any creasing.