Need some help choosing the best tyres

[GMac1]

I've just purchased a Mercedes V220d and it has brand new Kormoran winter tyres fitted. 245/40/18 100.
I obviously need to change them soon and now looking for the best tyres available. Looking at reviews, it seems Michelin crossclimate 2 are the highest rated?
Should I put on summer tyres and switch back in winter or buy all season?
I want to be transporting passengers in comfort at cruising speeds and would prefer the quietest tyres possible.
Any advice?

Thanks

[GMac1]

Should have said I live in central Scotland. I'd rather just have all year round tyres and keep the snow tyres just as back up.