Wheel Balancing

Hey Guys!
When I got two new tyres for the lcr (dunlop sp9000s) I told them to put the new ones on the back and the back on the front. They did that but when the missus was taking it home she was getting at lot of vibration through the steering wheel. Bloke from the garage came to the house took car round the bloke and agreed that something was wrong. He tok the car away and brought it back later that day.
I got home from work and noticed that one of the alloys was marked with whatever they used to get the rubber off
Anyway they agreed to refurbish the alloy so we left it with them while we went on holiday. Got the wheel fitted yesterday and all re-balanced AGAIN and the vibration is still there at about 70ish there is also a vibration that you can feel in the passenger footwell when going round a left hand corner as well as brake judder!

Is there something the garage is doing wrong i.e could the balance machince be out of calibraton or should I go elsewhere for a second opinon and bill the original garage. They are closed today so will be getting a phone call first thing tomorrow.

Any thoughts?

Cheers Guys

Got it looked by another garage and they started off by saying one off the alloys has a flat spot but after further investigation the tracking rod arm is either badly worn or broke. So it wasn't the balancing after all. the missus took it over cause I was at work.
The car got looked at by the AA and then a flatbed truck came and took the car away to out nearest SEAT dealer (70miles away).
Don't know what has caused it yet as the car is 22mths old but there was nothing wrong with it before it went to get new tyres

Well we picked the car up last nite and shes back to the way she was. The dealer replaced the tracking rod arm under warranty saying that it was just down to wear (cars done 29k), no impact damage or anything like that, could be down to a weak component!

Well thats that then.

Cheers