In searching through all the products of this type, I was curious and cautioned by all the reviews that said this product stained. But I'll get to that in a minute. It's always been difficult for me to find a mat due to my sink drain hole position. It's not in the center and not precisely in the corner. Most often, I have to measure and trim the edges and cut out the drain hole iin the correct spot. When I recieved the product and openned the bag, I was very surprised at how thick this mat was. It's between 2 to 3 mm's thick. That was important too me, due to having to cut and trim. Thickness is important. Now, the stains. I did notice that tomato based refuse did discolor the mat a bit. My wife loves asparagus and the juice left behind does stain the sink. I've always used Clorox Cleaner+Bleach spray to remove the stains from the sink. After I sprayed the sink, I sprayed both sides of the mat and put it back in the sink without rinsing either. As you can see by the photo, there's no discoloring after using this this product for 6 weeks. I rated this product 5 Stars in all categories. Normal deligence in cleaning and finding the right product to clean with, you should have no problems with stains.