Go with fx 6300 as it is way faster than i3.in future fx 6300 will really come in using in gaming due to good multithreated performance.fx 6300 is best under that range + you can upgrade to stream roller cpu in future while intel's lga is end
Honestly, both are very good! I don't think you'll be unhappy with either. The INtel has faster cores, but the AMD has 6 cores. The end result is that single/dual threaded tasks favor the intel and multi-threaded tasks favor the AMD.