i have managed to play the first two missions, now i'm currently "stuck" on the Cypress Flats mission
but my impressions up to this point are that this mode is amazing and could only get better as it becomes more stable
when i first got in, it gave me 10000 GTA$, dont know why but i think it was just a temporary thing, someone immediately started to chase me and tried to shoot them but i managed to kill them first. after that session, i got into the actual game. when i got to the Los Santos Customs-related mission, i tried to get a good sports car but apparently they are premium and aren't allowed initially :(
so i have a suckish sedan until i can get enough to buy my dream car <3