This official release is the most reliable and high-quality way to experience the game. Here are some key details:
Physical Blu-ray discs are dumped as an ISO image or an open folder structure (containing a PS3_GAME folder). Metal Gear Solid 4 was primarily distributed on a 50GB dual-layer Blu-ray disc. Emulators run this format by booting the virtual disc directory. Metal Gear Solid 4 Pkg Download