Welcome to the board from Southern California!!
I will feel it, if it has a good feel, not too thin or too stiff. Hold it up to the light, can you see through it? You don't want it real thin.
Stretch it a little, does it really stretch a lot?
Is it printed on the grain or is the printing really off?
Rub it between your fingers, or on a small white cloth, is there any color transfer? if so, put it back.
What is the price? If the regular price is $2-3 per yard, most likely it is not good quality greige goods. If it's on sale for that, that's a whole different story. I love a good sale!!!
I have several brands that I really like and trust and there are some brands out there that I don't even look at any more.