well i have more than one speedy b as this style is one of my staples that i use often. i love the 25 and 30 for different reasons. the 25 is great as a crossbody. the 30 is perfect when i want to carry a bit more. i use the 30 both on the shoulder and sometimes crossbody. the one advantage of the 30, besides capacity, is the wider mouth opening. the longer zip gives much better access to the contents. i love both de and mono, but i find the strap on the mono much softer. once the vachetta patinas the mono is quite care free i find. the de is care free from the beginning. the de also is a bit more discreet if you want a bag that does not scream lv. either way they are all great bags, but consider how you want to carry it, how much you carry, and how important visible access to the contents is to you. best of luck and let us know what you decide : )