I know this is an old thread but my experience with SMG Tonbridge goes back to 2015 so it's probably appropriate to add a comment.
Why did we end up going to SMG Tonbridge in the first place?
After a lengthy period of research during which we had visited at least half a dozen dealers, SMG were one of two that we found to be both knowledgeable and extremely helpful. The other dealership that were excellent was South Hereford Garages in Hereford. All the rest were truly awful. All these bad dealers had one thing in common: they showed between little and no interest in our custom and made little effort to sell their product. One even recommended that we went elsewhere!
What did SMG Tonbridge do to make us feel valued?
We dealt with Laine Watts who is genuinely a very nice chap. Since then we have met their whole sales team on other occasions and they are all a very friendly and accommodating bunch. Laine spent several hours explaning every facet of their California SE demonstrator even though we had gone there to look into buying a Caravelle! He is extremely knoweagble and quickly persuaded us that the California was right for us. We bought that demo. Since then we have purchased two further Calis from SMG Tonbridge, both Beaches and both from Laine. Every time he spent a lot of time explaining everything and on all occasions he gave us a very good discount. All three vans were faultlessly prepared and the handovers were always comprehensive.
What about other SMG Tonbridge services?
On our current van I wanted to retro fit the chrome pack which is quite an involved thing to order. SMG's star parts chap is Chris who went the extra mile to sort things out and give a very healthy discount. He is also a very nice chap. We have had cause to use him on several occasions and he has always been extremely helpful.
Servicing - has always been straight forward with no issues so far.
Warranty claims - Here's where we have had some issues. During our ownership the three vans have needed very little attention but there have been several warranty issues:
1. Alloy wheel centre caps delaminating.
2. Airbag warning light. The passenger seat wiring harness pulled apart when swivelled.
3. Rattling sound from somewhere near the sliding door.
4. 3 x picnic chair failures.
In every case SMG initially claimed that these weren't warranty items. However, after referring items 1,2 and 3 to VW Customer Services, items 2 and 3 were warranty items and were fixed accordingly. Item one was classed as a wear and tear item but after I argued that it clearly wasn't they coughed up the full replacement costs as a good will gesture. They replaced the chairs without quibble after initialIy stating that they weren't covered. I get the impression that the servicing department has to run at a profit and if items aren't genuine warranty claims then VW won't cover the cost so the service department ends up footing the bill thereby reducing that profit. I might be wrong on this but their first line of defence always seems to be to tell the customer that the issue isn't covered under warranty. If you read the advertising blurb, with few exceptions, the original factory warranty and the extended factory warranty are quite clear on this. If it goes wrong or breaks then it should be covered.
So our experience of the team at SMG Tonbridge is excellent and we would thoroughly recommend them. However, be prepared to fight your corner over warranty stuff. I agree about the parking and suggest insisting on a before and after walk round with the service staff with notes being taken on the condition of the vehicle when you drop it off. Any damage will become obvious when you pick it up and difficult to deny. Personally, I always present them with a clean van to make this task easier and I always instruct them NOT too wash the van.