This comes up ALOT. Upgrade path I3, gaming into the future when dual cores are not enough, FX-6300, and please don't tell me how much "better" the I3 is, cause yes its better, alot better in single and dual threaded applications, but is below the minimum requirements for Witcher 3, Star Citizen and many more coming down the road, Dual Cores, Hyperthreaded or not, are a no go for me.
The FX line on the AM3+ socket is pretty dead, its not going anywhere, if you think your going to have the cash to get into an I5 soon, then go with the I3, or save a bit and get an I5-4460
As for 144fps, thats a big ask for a budget CPU