While a porcelain kitchen sink looks more attractive than stainless steel, it is quite more difficult to clean when it gets a stain. That’s my problem right now with our own sink. For some reason, some dark spots have settled on the floor of the sink and it looks dingy and dirty. I’ve missed the stainless sink we had back in our old place because I really didn’t have to exert much effort in keeping it tidy and clean. I have read that mixing some liquid dish washing detergent with liquid chlorine bleach and some white vinegar and just let it soak overnight will usually help remove the stains on porcelain sinks so I might try to do that and see if it works.