My ecstas wore out really fast and didn't seem to grip the road very well. I guess they were worth the half the price of other tires I paid for them, but I never had excessive noise on the highway. I replaced them with a set of Cooper Lifeliner SLEs. They are much more of a touring tire that make the ride nicer (yet they grip the road better in terms of less squealing).
I thought that Hunter rfb machine was supposed to pick out defects in the tires pretty well. At least that's what their web site claims. Could be just that your 70 mph shimmy is so tight it makes noise instead of shaking your car like a terrier with a rat
