It's been 5 years since I had an alignment. Changed my rims & tires over a few years ago(used) & didn't bother. Well I took a 500 mile road trip in my X. I got to my destination & just happened to notice by accident the inside edges on my tires were bald. There were no signs otherwise, no shakes, shimmies or pulling. I had to drive another 300 miles to get back home like this praying they wouldn't pop. Not a good feeling.