No don't do that. Ken Rockwell is anything but an authoritative source. You can tell by the price. If good ones cost $600-1500, then which ones cost $150 or $200?
These lenses have severe distortion -at least the two of them that I have do - as well as serious softness in the corners and light fall off. They are also quite slow. They do work and they may be fine for a beginner that doesn't know the difference. But they aren't good lenses.
I'm not aware of Sigma making anything that cheap or bad but it is possible, I suppose. My experience with the Sigma, Tamron etc. brands is that they are normally just fine optically and weaker than the Nikkors physically without fit and finish and feel like the Nikkors. Generally, I consider them good values. I don't consider the Nikon kit lenses to be good values. Value is a subjective thing, so that is an opinion. The distortion in the lenses, however, is easily demonstrated. It is not an opinion. Good luck.