They have now introduced a system whereby one can apply for a card after paying a set fee. When driving through the toll instead of having to stop, ones car registration is read and then the barrier opens allowing the driver to proceed without any delay in operating the machine and physically paying the set toll tarriff. The toll payment is taken from your credit card or similar. Sounds great but...

I have heard that some people have had problems with it not working or there is a dispute on the amount to pay.
Does anyone have practical experience on this issue?
Phil