Changed out my Bridgestones last week after 13000 miles, 2 still had another 7 or 8k in them but unfortunately a nail through the edge made one useless.
Went for the PS4s from Costco for £426 but got a £50 voucher in return - I was thinking of spending that on some Levi's but apparently it's going on food for this weekends BBQ
The tyre fitters were raving about how good the PS4s are and said you can feel the difference in the sidewalls when fitting them. They both had PS4s fitted to their own cars.
First thing i noticed is the tyre noise - its gone!
They feel good when turning in but I haven't done many miles yet and obviously can't comment on wet weather handling.
I think the diff does mask shortcomings of the Bridgestones - I could hear (more than feel) the tyres slipping in the wet when in the lower gears before and that had to be down to the diff.