My vote goes for the Manhattan PM as well, such a lovely bag!
Also regarding the leather, the leather will be the same color on all bags (+/- 1/10 of a shade) if you are getting it new from the boutique unless you get the floor display one which would have developed some patina.
I had a hard time decided between those two, but ended up getting the Hudson. I prefer a shoulder strap, but I do buy handbags, too. It's best to go to the LV boutique and ask the SA if you can put your items into each bag because you're having trouble deciding between the two. This is what I did. The Hudson allows you to see/find everything in your bag. The Manhattan PM doesn't open wide enough for me. What I liked about the Manhattan that I don't like about the Hudson is the size of the two pockets. The Manhattan pockets are bigger and I could fit my cellphone into them. I can't fit my phone into the exterior pockets on my Hudson bag, but I tried my sister's phone and hers fit. If you have a long wallet you may have a problem with the Manhattan PM. Both of these bags are expensive. I think you should compare side by side and try them on for size before making a decision.