Hi Kizzy! I'm 5", 92 lbs and the jumbo fits very well on me. I also have a black lambskin m/l classic flap. IMHO, the lambskin m/l flap is more formal, whereas my caviar jumbo is more casual. And a red jumbo is to die for!
I am also 5' and about 85 lbs. The jumbo was overwhelming at first. I actually thought of selling it within 24 hours of acquiring it.
I shortened the straps and it sorta grew on me. I think it has more character than the medium size and more practical, too.