My recap/thoughts so far:
As there hasn't been enough mileage to be conclusive enough as feedback/a review, I can only explain what I've experienced so far. As we all know, the protective coating needs to be worn off before you experience the actual capabilities of the tyres. As such, someone decided to drive over into my lane round a large roundabout junction, causing me to hit the brakes and seeing the traction control light flicker.
I'm about 100 miles into the tyres over quite some time and I can say that this would be a big step up in comparison to the Sessanta, the sidewall profile, construction and build are very different, Sessanta would be firm but the 651S are rock solid. Volume wise, it's rated pretty well at 69dB but the most notable experience I've had is with a particular roundabout near me
In the previous Sessanta tyres they provide great feedback through the steering to me, I can feel when it's nearing its limit of traction and when it breaks traction. If I push it hard, I can feel the slip and have a very controlled slide. With the 651S they grip and grip and grip. It's until I upset the power delivery with the clutch I can feel the back end loosening for some play. It gives such great feedback.
Removing my custom exhaust was a sad moment as I particularly enjoyed the Helmholtz resonators. As a whole, the exhaust had a great sound and you can definitely tell that the resonators were doing their job with muting the tone. Once you reach a specific rev/pitch and hit the cruise control, you can mute the exhaust and have a phone conversation. Great for those motorway drives.
The MXP Comp RS Ti doesn't have this, it's just a centre silencer and 2 cans and immediately I can hear it's very much a free flowing exhaust. It sounds angry! I think I'm warming to the titanium exhaust tips on my car, I never really gave them much thought when picking exhaust systems as a polished setup just looks great. However I appreciate the look of them with the amount of poke I've given them on the system through the Rocket Bunny diffuser.
The volume of the exhaust was definitely louder than my previous system and I felt I needed to get some mileage through them and learn about it more, modulating the throttle to find quiet areas and the like. Wide open throttle does sound rather tasty! But now learning more about how I use the exhaust, I feel I can drive it quieter than before.