I've never heard of it until now, but I'm definitely intrigued.
It looks like prices are set by the seller, so you can set your prices as high or low as you want. Also, please note that shipping is INCLUDED in the seller's price. So it may look like the fabric is expensive, but it includes shipping costs.
Only thing that gives me pause is how good (or bad) the sellers are at taking photos of the fabric. Hopefully the colors are true!
The good news for sellers is their rate is lower than Etsy. My thoughts - what do you have to lose? List a couple of things and see what happens.