The fact that it's a Golf R is totally irrelevant. It is not more acceptable for a trusted third party to break the speed limit in a customer's Golf R than it is in a Nissan Micra.
Speeding in a customer's car is unprofessional and risky, both in terms of possibility of an incident and the potential for an embarrassing speeding ticket.
I would without a doubt be round my dealer with the video to voice my dissatisfaction.
If that makes me a stuffy git, so be it. It's my car and I'd be extremely annoyed about it. A senior manager at OcUK saying it's OK to ignore a 50mph limit as long as you reckon the road lends itself is just the icing on the cake.
And lol at hurfdurf's 'people don't know what genuinely sporty means'; like the sportier the car the more OK it is for the dealer to abuse it

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