Bowls from the 80's and before had a large pool of water. There was almost no porcelain you could hit.Are the skid marks just a limitation with low flush toilets, or is this a drawback on the Toto brand?
New bowls using less water have more surface to hit.
This is the way since the beggining of the 1990's
I use a liquid toilet bowl cleaner. Clorox and Lysol have worked. I have not tried Pine Sol.