@LukeAlmighty You don't really get anything for doing it except an achievement. I'm kind of an achievement junkie so it was worth it for me. I already did it years ago on the Xbox 360 but I never did the MP achievements because the MP for GTA 4 was a hack fest and the games framterate on console made the game not fun to play.
With that said the PC port is a pain in the ass to set up had to use DXVK .dll convertor files and use a bunch of launch flags to get the game to use the full 4GB of system memory it needs (32-bit app) and lock the frame rate to 45FPS since the engine becomes unstable and has game breaking bugs if it exceeds 48FPS.
Well they did finally remove GFWL (Games for Windows Live) DRM but it still had Steamworks and Social Club ( Trust me GTA 4 having social club is retarded because it's a single player game ). They re-released 2020 port on Steam removed all MP functions from the game because it no longer worked ( tied to GFWL ).