Never having played Vampire the masquerade I cn anīt sya that any game is better then the other but I can say this. From playing alot of different games you get more ideas, you develope yourself a bit more. Try to play a campaign of Vampire and read the rules for 3:ed, then play a game of 3:ed, read more rules for Vampire, and so on. Finally after a couple of campaigns you will see that your way of playing have changed alot and that the versality in having two games make for more interesting meetings with your friends and you wonīt grow boored with either of them or you might find one alot better and more fun then the other.
I think you should go for two different games actually. Gives you more ideas and can make new campaigns more rewarding both for playing and leading. However, do that which you like the most and try try and try!
Good luck with your RPG experience!