I also have VB, and my compressor is quite noisy, but I believe it is on its last legs and I have a replacement waiting in my garage to fit when it fails. It is quite annoying when parking and it makes final adjustments to the ride height after passengers exit the van. Otherwise, I don’t notice it.
My VB Air was fitted about 6-7 years ago and I wouldn’t be without it. It doesn’t go dramatically low, and certainly doesn’t adjust fast. But it keeps my van level when I have a load in the back or my motorbike on the rear rack. It auto levels for camping, has a car park mode for those low multi-storey car parks and an off-road mode for those extremely pot-holed country car parks.
However, I did have a failure of my front struts 18 months ago. This was apparently due to a known issue with the early struts fitted to the T6, and I was given a 50% goodwill reduction by VB on the new, and modified, front struts. It was during the replacement of the front struts that I was told that my compressor was looking like it had overheated (probably while trying to compensate for the failed struts) and probably wouldn’t last long.