XL size is 6" x 4" x 2.5", holds camera, camera plate (should hold L bracketed camera), spare battery, spare card, lens hood. Closeup lens will fit in as well, if spare battery and cards moved to some other pocket, but as the closeup lens has its own small protective case, why bother? The Hoodman is dangling off the shoulder strap.
Thanks to Nancy for that suggestion. The XL size is indeed necessary for the DP2M with the Milich L-bracket and grip. If you are going minimalist, the Optech Hipster Large will handle a naked DP2M with lens cap only. Another alternative that accommodates the camera with L-bracket and grip plus a 49mm collapsable rubber lens hood and cap is the Ape Case AC150. The Ape Case takes the camera vertically, while the Optech Hipster Pouches open along the long side.