Many user-uploaded saves are damaged or incomplete. A corrupt file will freeze your game at the loading screen. Only download from reputable sources with user comments and high download counts.
Every character has a unique CGI ending. While you can watch these on YouTube, loading a 100% save lets you view them directly in the Theater Mode on your PS2 or emulator. Tekken 5 100 Save Game Ps2
Tekken 5 introduced a deep customization system. You can change hairstyles, add auras, equip katanas, sunglasses, and even silly items like plungers. Grinding for Gold (G) to buy everything in the Character Customization Shop takes dozens of hours. A 100% save game unlocks every single item for every character. Many user-uploaded saves are damaged or incomplete