MarkyGBR

FiveM is all a bit of a mystery really.
It might be released, and work-- but what's actually going on appears to be a big mystery, I can't find anywhere that actually says what's happening, what's coming and what's getting released so in that aspect it doesn't really appeal to the casual gamer. That being said, it is working and functional unlike GTA-MP, so it has that bonus.
Where-as GTA-MP appears to be a lot more casual gamer/user friendly, in that they provide consistent updates. Unfortunately not much evidence that its functional, but If they can pull it off, and go ahead with a release to the public before FiveM decides what it's doing, I reckon it'll be the bigger hit, just because it's more accessible. 
Then again it might turn out like SA-MP and MTA did. MTA nowadays is clearly more accessible, and written in a superior coding language, with more possibilities. But SA-MP has always been the most popular. Which could happen between these two, but only time will tell I guess.
 
Personally I'm more hyped for GTA-MP but that's just because I'm stupid enough to trust what they are doing in these 'dev blogs'.

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