the BV is too big for me. i think it looks terrible when i see someone wearing one & they don't have enough stuff to fill it. the BV has the worst sag factor of all the bags, imo.
I have this bag and I don't like sag either, so I added a cardboard bottom to my BV Transporto and I use a Purseket as well. It looks good!! Plus I carry a bunch of stuff in my bag, so the cardboard bottom works well to prevent sagging.