As I said, I simply have no interest in F2P games that reward those that pay with gameplay perks. I find XP/unlock systems to be a tedious form of gameplay. I have no problem with charging for cosmetic perks though, which is exactly what Valve is doing with Dota 2.
F2P has little interest to me. I am happy to pay for a game knowing that if I play against others I'm on an equal playing field. As soon as you allow people to pay to unlock XP and money quicker you throw balance out the window. The very fact that the top tier is $120 speaks volumes and it's what pissed me off about Age Of Empires Online.
If you're happy to play against other people that are paying for an advantage over you then that's fine. But that shit isn't for me.