Vacuuming over a period of time will tell you alot of things about the seam..... for instance, if the seam keeps loosing it's fibers every time you vacuum that tells you that the seam was NOT installed correctly and before long the seam will become more noticable every time you vacuum. On the other hand YOU have to make sure that you didn't buy cheap carpet, so cheap that the backing doesn't hold the knap well. anywho, I'll quiet down so i don't get myself into trouble..