You are comparing two different generations of CPU. If you want to compare another cpu with the i5 4570 you should be looking at the i5 4670K. That's the cpu that is the same generation (same motherboard socket type).
So it's about an extra $40 to get the 4670K. If you are interested in overclocking it's really worth it. Especially in a few years when the CPU starts getting dated, it's nice to have the option to overclock it. However, if you know you will never overclock, the 4570 is still a very powerful CPU for today's games.
The other part to keep in mind, that may help you make the decision, is if you are going with the 4570 then you also have the option of going with an H87 chipset motherboard instead of a Z87. This would bring the overall cost of your system even lower if you are looking to save costs. If you get the 4670K version, you definitely want the Z87 chipset motherboard as that is what allows you to overclock. The Z87 boards cost a little more than the H87 boards. So there's some more food for thought.