Well, those are my two favorite MbMJ bags, I have 1 Hillier and 2 Faridahs....that said I think that the Faridah is my favorite, but only by a little. Here's why: The Faridah's strap is wide and flat, it's a bit more comfortable than the Hillier's rolled strap (but you could always use the longer one) and the front pockets on the Faridah are so nice for keys, phone, etc. Sometimes it's hard to find my phone, keys in the Hillier since there is only one small zip pocket on the inside.
Why don't you just get both?!