I have had difficulty getting my tires balanced since I got them...I have had Sears do the "lifetime" re-balancing every few months for 40,000 miles now, without ever truly being vibration free.

So, last week I had a buddy of mine drive next to me on the freeway...he was able to visually spot one tire hopping. I swapped it with the spare and suddenly I have a vibration-free ride...it's almost eerie, I am so used to the vibe. Now I just gotta take the spare in to get rebalanced, they won't be touching the others!

So give the visual method a try, if your vibration is a bad as you say it should be easy to see which ones are bouncing...