Looking to get into Tribes multiplayer but dont know which one to play

As the title says ive been meaning to get into tribes but i dont know which one has the most active multiplayer scene, im fine with just playing on weekends or a smaller playerbase but im curious on which one is played most and what the big difference is between all of them

for further context ive only really played the tribes 3 beta and i thought it was quite fun and i wanted to get into the series more