Both had classic debut albums but 50 never could match the hype of GRODT. 50's numbers slowly started sliding with each album he dropped while X's numbers kept going up. Ruff Ryders imo, had DMX, Eve, & D-Block (The Lox). G-Unit had 50, Banks, Game, & Buck. On a talent level both squads were equal. They both had short runs in their prime.
This pretty much is a slight edge to Ruff Ryders only because they got the street game back sparking after all the soft party & bs songs coming from Bad Boy in '97 which started a new movement & sound. Ruff Ryders had some competition with Roc-a-Fella/Cash Money being that they blew up at the same time. By the time G-Unit came around they had no competition and hip-hop was slowly turning into TRL/Pop music so G-Unit had an easier road to just dominate when they came through.
That's not true. Niggas tend to forget how big Murder Inc was prior to 50 Cent. DMX and 50 had beef with Ja, Fif did what X couldn't. The Roc kinda killed themselves, but they were still comp for Fif at the time too.
Then you gotta give Fif (and wayne) credit for creating the lane for mixtapes.