I'm putting together a new build and just ordered an i5 4670 as my processor.
Most comments here have said that the stock fan will be just fine as long as I don't overclock (which I'm not planning to do) and all the people that reviewed the product on newegg said that the only con of the cpu was the fan...
Anyone have any insight?
If you have a larger case with several (3 or more) case fans, the stock cooler will generally be fine. If the case is somewhat cramped and you've got other sources of heat such as video card(s) though, a decent aftermarket cooled like the Evo 212 is a good idea.
the only reason to replace the stock fan of a non-overclocking cpu would be to reduce the volume of it. There's plenty of cheap little cpu coolers which will be much quieter than the stock