One of you told me back then that there are not more border controls does that mean once i hit the motorway i can just keep going till i reach Poland?
Theoretically the last border control you will face will be when you leave the station, then you can drive straight to Ustron.
I've been getting pulled over a lot lately crossing from Poland to Germany. And with UK plates, you might draw some attention crossing from Holland to Germany. They're like mobile passport checking huts :)
Make sure that you stay out of the Ruhr area during rush hour, and you should be good to go as far as traffic is concerned. The highways in eastern Germany and Poland are nice, and there usually isn't any problem with traffic.