Great store... one of the most successful Discount Tires in the country. Great management as well. I would recommend them as well.
Which store do you use. I trained most of the managers and owners in the Denver and surrounding area in the 90's.
Big O thrives on making customers first. Not just saying it. Generally you won't go wrong there. Also, the management at Big O knows how to re-calibrate their balancing equipment and does so regularly.
It is possible that the tires were balanced right and you have a bad tire or maybe a few.... it does happen from all makes.