Laptimes with a skilled driver aside...good shocks are just a lot more fun and confidence inspiring IMO. That also tends to translate into more consistent times for a newer driver.
There are plenty of time attack cars on crappy shocks and sticky tires that can put in a good lap. But watch the in-car video and it's a battle with thin margins. Not always fun or consistent lap after lap (without even mentioning shock fade). The cars with good shocks and enough travel and a nice balance make for a happy driver and longer lasting tires and drama-free consistent lap times.
Anyway, really love my MPS4S and the older MPSS on the street but it's less of a track tire and more of a tire you can track if you need to.
- Andrew