Here's a picture of our largest watermelon to date, this season (I'm guessing it's 17lbs; there are some potential contenders). It's not huge, but it's large for our garden. It has pink flesh and black seeds. It may, or may not, have a winter watermelon in its ancestry.
This was one of the first ripe watermelons, this season. I had it in the refrigerator for a while. It was good, but not super sweet or anything. A little under-sweet, but definitely still good. It may have had more flavor and sugar if grown in another spot, I'm guessing. It's near where the Coldset tomato was last year (which didn't have a lot of flavor there, either, although the fruits got large and nice).