Bad wheelbearings roar or growl with increasing speed. At some point they finally get loud enough that you can't bear it so you change them. Once you change them you realize that they've been making noise for a long time because your car is sooo much quieter.
Just drive the thing! You won't have it long enough to worry about it being out of warranty anyways. You trade in every 3 years or so.
Now if it was me then I have reason to worry since I keep it till it dies.
Amkeer I do plan on keeping this car for quite sometime. Unless I can't control myself and go buy a Mustang in a few years. Seriously though, I want to keep this car a long time. I'm going to have to with some up comming changes.