My first birkin was a 40cm black togo, I adore the bag but have to say... I hardly use it anymore because of how heavy it is. I have a fondness for it because it was my first, but I am much happier with both my 35cm. I am 5'8, thin, and find the 30cm a bit to small for my frame I think the 35 is perfect. I think you may find the 40 oppressive. Good luck!!!