I've had many Days and quite a few Works. I love both, but if I could have only one Bal it would, without a doubt, be a Day. It is by far, the most comfortable, carefree bag I've ever carried. I have no trouble finding what I put in there, because I put all my little junks, bits and pieces into a MU, which is easily reachable. The only exception are my keys, and they are on a
Coach key chain that includes a large fur ball, also easily accessible by touch.
I love the size and ease of stuffing a Work too. Getting in and seeing what is inside is much easier than the Day. It opens up wide and doesn't have the City "ears," to get in the way. I've only had 05s and 06s, so the handles are a bit smaller. I almost always carry them by the handles. As they age they do stretch a bit, and can go over my bare shoulder... The double handle is annoying on the shoulder, as the outside one is forever falling down. The bottom on the older bags will eventually sag, but it does have that stiff base in there, so it needs to be really well worn before it droops the way you (and I) really like. Only my most beat up Work had something close to a nice saggy bottom.
Sadly, there is no one perfect bag. That's partly why so many of us can't stop at one.
I'm sure you will love whichever you end up getting.. also sure you'll want the other.