I don't think that the size or length of the lips would matter much as long as the woman's hygiene is good. Just like an uncircumcised man, a woman with longer lips might have to pay a little more attention down there. Personally, one of the best lovers I ever had had long lips and was a little self conscious of them. However, once I showed her that I thought they were sexy, she was VERY grateful!
She loved it when I sucked on them while my tongue was inside her. I don't remember if it was the feeling of it or just that she loved that enjoyed her lips. Come to think of it she also tasted better then any other woman I ever ate. Any other people have a similar experience?