Having both an E/W and WOCs, I prefer the WOC because of it's versatility. You can use it as a small messenger, clutch, evening bag or also as a wallet in a larger handbag. The WOC actually can hold more than you would think. I can fit my small 4" x6"? Chanel ring agenda, a big cell phone (Virgin Switchback), an epi-Pen, crayons, and a bag of M&M's.
I dislike the E/W shape because the horizontal line visually draws attention to the width of my bottom.