Just hate those threads where people comapre those 2 games..but anyway..
After playing 6 years of Dota and 1 and half year of Dota 2 what should I say..
Try games get into it and see by yourself what is better.
Before 4 days was Dota 2 International tournament too bad if you missed,over 1 milion people was watching and you could get into game.
Anyway check vods,final game 5 Alliance vs NaVi was amazing you should check that one for sure.
Never played LoL so like I already told you it is best that you try both games and then decide what you like and what is "best" for you.