Congrats!! I was in your same position a few months ago. The Soho was the first Gucci bag I fell in love with, but I ended up going with the red Marmont bag cos I wanted something a little fancier. If I had unlimited funds, I would get them both!
I just found this post, I had the same dilemma; I ended up getting the Red Disco 'cause I feel i always buy my bags in a "safe" color, and with this one i was feeling "daring" LOL Congrats on your new baby.