I have the antigona (well, just sold it actually) and the SDJ. I prefer the SDJ as it's easier to get in and out of. I'm not a fan of the zipper on the antigona - I had the mini size and I didn't find that it zipped smoothly and it was also difficult to get in and out of because the zipper would scratch me every time. I have the small and baby SDJs and prefer the baby size.
Can't speak about the PM as I don't have it, but I do have the marmont. It's a nice, trendy bag that's easy to just throw on, but if I had a choice between the two, I'd go with the PM.