I have six half moon WOC's. I wouldn't trade any of them for the world.
I like them better than the classic WOCs because:
1) they carry more in the "main" compartment
2) the card pockets aren't as tight as the classic WOC's
3) the "gusseted" side isn't actually gusseted but its own reinforced exterior panel, making it more durable
4) the iPhone 6S+ fits in the FRONT pocket of the muliple pockets of the WOC. In the classic model, you have to put the phone in the MAIN compartment because the front compartment will not fit the phone anymore
5) the bag is much more durable because the weight of the bag is carried by the main compartment, not the top flap. If you look at how the chain connects to the bag, the chain connects to the base, not the top flap.
6) Because of #5, you can open the WOC much more easily, and the bag won't start to move once you open it because the top flap is not connected to the chain like in the classic WOC. In the classic woc, depending on how heavy the WOC is, once you open it, the bag will move backward
7) you can open and close with one hand, because of the weight dynamics above but also because the button snap is a larger magnetic button snap that self-guides to close.
The only "con" is that oftentimes the magnetic snap closure is too strong, which can risk weakening the soft caviar leather around it. My current fix: cut a piece of scotch tape into a circle and put it on one side of the clasp and then press down hard to close. Weakens the magnet just enough.