So after having 4 new Michelin Latitude Tour HP's fitted and having driven the car over 100 miles, I feel I can safely share my thoughts on them. My car originally had the Dunlop SP Sport 270 tyres on them from the factory so I am directly comparing to those.
Firstly, the ride. From what I can tell so far, the Michelin's ride slightly softer than the Dunlops and soak the bumps slightly better. Its not hugely noticeable but atleast its an improvement.
Then there's the cabin noise! These tyres are rated at 69dB with the previous Dunlops rated at 71dB. It was the main reason I bought these tyres as the Dunlops could be heard rumbling away, albeit a very quiet rumble. With the new Michelin's there is no noise from the tyres at all making the already quiet RX450h almost eerily quiet. Its very noticeable so if you want a quiet tyre, these are the ones to get.
Handling remains unchanged. Slightly better due to more grip but thats because they have more tread on them. The Michelin's do seem to have a wider tread though, even though they are OEM 235/55 r19 fitment and slightly stick out compared to the rim. I dont mind that - itll probably save me from the dreaded kerbs!
Finally, the price. These tyres were relatively cheap at £123 each from Oponeo and fitting was a mere £50 for all 4. That makes it £136.50 a tyre - a good £60+ saving on each tyre compared to if the original Dunlops were purchased at Lexus.
I cannot say how they will wear as its too early and I havent had a chance to test them in the wet yet so stay tuned......