Believe it or not there are nuances in tire design that interact with the how the suspension is tuned on different vehicles. I ran Michelin LTX on the burb for a year and they were the worst tire I ever owned. JBarca reported similar results on his 2500 burb. I know Michelin makes good tires, I have them on my two other cars. Guys run them on Ford trucks and love them. But, for some reason, they are not a good match with a 2500 burb. Same size, E-rated, etc.
JoeTampa, chances are in your favor that the tires will break in and be fine, hopefully before your vacation trip.