So far they have been great. When I bought my van they diagnosed a nasty issue with the charge cooler it had been sold to me with and we’re very good at giving me a temporary fix so I could drive it back to the garage that sold it to me.
But apart from that I’ve only had servicing and cambelt change through them. They have been quite honest about a bit of clutch judder on my van and tell you what is safe to live with and what needs sorting straight away.
They’re probably not the cheapest around but cheaper and better than a main dealer in my experience. They also run a T6 themselves and the owner talks fondly about Transporters in general which I think helps. I’ve always found them honest and reliable which gets my vote.