I suspect many of you know this already but if you have not used a Hunter Road Force machine when getting new tyres, you should give it a try. It can spot a problem with the wheel or tyre, highlighting the need to repair / replace the former or reject the latter (my tyre place uses print outs when sending tyres back to the wholesaler). And, given that no wheel or tyre is perfect, it will advise on ideal mounting (by rotating the tyre on the rim) to minimise any vibration (separate from balancing) - something that is routinely done by manufacturers with new cars and one reason why they are smoother out of the showroom that they often are after buying new tyres.
I know I should like a fanboy but since a HRF transformed the ride on my wife's 997 I would not have tyres fitted any other way. And I don't run a tyre fitters either
Just been through the process again today and car is as smooth as silk - and 20s still perfectly round after 30k.