Michelin really ballsed the naming convention up on the Pilot Sports.
First you had the original Pilot Sports, which were good. Then you had the Pilot Sport 2s, which were exceptional. They then quickly dropped the original tyres, and then stopped putting the '2' on the MPS2 which just confused everyone trying to order a new pair.
Then they started trading on the good name of the MPS2, and brought out the MPS3. These were available in much smaller sizes, and aimed at the lower priced car market. They were still good, but they weren't MPS2 good.
Then came the MPSS, which are just about the best road tyre you can get today bar none. Miles better than anything else with the PS name, but have zero relation to the still-going MPS2 and MPS3 in anything other than name.