My 2011 EcoBoost SC is quieter than our 2005 Volvo XC90 and rides better. Doesn't drive or handle better obviously, it's just smoother and quieter and gets better gas mileage. And it's a 4x4. I'm pretty happy with that part.
I also have heard that bug deflectors can cause problems but if it's not that and you've got noticeable noise at only 50-55 there's a leak somewhere.
2013 Porsche Cayenne TDI Diesel
2011 Gray/Silver SC XLT 4x4 ECOBusted, Custom 4x4 Decal/Stripe
FX4 Wheels w/Michelin MS/2s
Spray in liner and Pace Edwards Jackrabbit Tonneau
Kenwood Excelon XR-4S 120/4W amp and 4 6x8s