you have to take time to consider if you really want to know what people think when you ask this sort of question on a forum. Not just a pc hardware forum, but any forum. It's never wise to go and choose/buy something and then ask for critique as you will get roasted every time.
If there is one, universal, truth right now in the PC hardware world, is that the current fx series are pound for pound some of the worst cpu's ever released alongside their competition. We all wanted them to be better and we all wanted the radically different cpu design to work and better intels offerings but the truth is they didnt. They didnt outperform even AMD's own offerings in many tasks. the 6-core phenomsII's still remain the best cpus AMD have right now, better then the fx8 for the majority of tasks you would perform as a home user. The fx4's.....well, they are not as good as the quad core phenom IIs. It's a bitter disappointment for some of us but those are the facts.
Slow they might not be, not outright anyway, but there is very little to justify buying a more expensive, slower, more power hungry cpu when there is simply better available.
I would agree with this. Is it fair to say that an informed decision would likely not lead to buying an fx4 cpu or a 560ti?