Well, my OEM Michelin MXM4's are about done at around 21,000 miles. I'm strongly considering Bridgestone Turanza Serenity Plus this time around, but I'm having a hard time getting real head to head comparisons against the MXM4's. For example, TireRack's comparison has the Serenity Plus against the Michelin Premier A/S and the MXM4 against the older Serenity's. The older Serenity's are not LRR and the new Plus should be both quieter and is rated as LRR for better efficiency. I don't really drive my Model S in bad weather, so I am potentially up for putting on ultra high performance all season tires. The question I have is if I go with something like the Continental ExtremeContact DSW 06 or the Michelin Pilot Sport A/S, just how much louder is a tire like that over the MXM4's? Thanks much for any insights people can provide.