The Primacy 4 are performing well
I must say I don't have a real comparison with the Eurostars, as the car was parked for the first two days due to torrential rain in Lahore and later only drove from DHA to J Rashid & Co at Nila Gumbad for change of tyres.
The drive felt smoother comparatively on the way back. I was advised to keep the tyre pressure at 32psi
The tyres are definitely not sticking out of the sides and cosmetically look good.
There appear to be better stearing control and road grip.
The car itself if better insulated compared to my outgoing Aspire, so difficult to confirm that the Michelin's are quieter than the Eurostars.
As regards fuel economy, the car has only driven 250km so far so will have the initial estimate at the first refill, but as everyone suggests it gets better after 1000 kms.
Overall I'm pleased with the decision of changing the tyres to Primacy 4.