Congrats on your new bag, she's beautiful and they both look great on you! I do not think anything is wrong with wanting both in different sizes and hardware color, they are both very different looks. I feel like bc of the size the jumbo can be dressed down and good for casual everyday use. I love the medium for a little dressier occasions, bc of the smaller more compact size. You can never go wrong with a black classic flap, I say keep both!
My first CF was black jumbo w shw but I ended up selling for jumbo with ghw, now I wish I had kept the jumbo in silver and bought a medium with ghw =( Good luck with your decision, pls keep us posted!