Decent sub-£5k barge with air suspension?

[Chromegrill]

Had a thing about air suspension ever since floating several hundred miles along the motorway in a Citroen XM many years ago in a friend's car and thinking it was the most comfortable few hours I'd ever spent in a car, bar none. Looking to change my present car and sizing up which cars in my budget (up to £5000) to look at. Other preconditions: must be petrol and must be automatic. Options at first glance include:

Citroen C5 (pre-2008)
Citroen C6
Audi A8
Jaguar XJ X350
Land Rover
Lexus LS430
Lexus RX300 (2003 onwards)
Phaeton

However, as I live and drive in a big inner city I don't fancy trying to park most of the above. And as I need the car for work that rules out the Land Rover or Citroen which would live permanently in the local mechanic's waiting to be fixed. A few E class Mercs seem to have air suspension but very few ads say it's fitted so either it's very rare or it's rusted away (budget pretty much excludes any E class post 2006). There must be others out there besides those in my list - any suggestions for a floaty magic carpet ride in an elderly automatic petrol luxobarge that's small enough to drive and park in a big city?

[Chromegrill]

Thanks - not looking good then. Keeping the XM as a benchmark (but as car has to be my daily commuter I think the XM is too old and potentially too unreliable to fit the bill) I tried the newest C5 which I also thought was pretty good. Except there is no petrol version, and my dislike for diesels goes beyond their polluting characteristics.

I also gave the XJ X350 a try and really liked it, but on balance it's probably not a great choice as a daily commuter around town.

So perhaps I should be asking, which other cars' suspensions come closest to Citroen's hydropneumatic? As even that is being phased out I have to assume that there are other means besides nitrogen filled rubber spheres or air compressors to create a floaty ride.

[Chromegrill]

Who said W211 E500? I like that man. Had a look at the specs - ticks all the boxes, leather check. Tasteful wood check. V8 check. Not sure I need five litres of engine thumping away in the city centre but similar size car to my present Rover 75 and most bizarrely the insurance seems to be cheaper too. I tried test driving an X350 (lovely floating sensation but a bit big for my circumstances) and the Lexus GS300 which is far too sensible a car. The E500s aren't that much more to buy and have "want it" all over them.

Are there any major pitfalls to be aware of? Like, is it worth risking any W211 built before mid 2006 or will it rust away before my eyes while the electrics disappear in a flash of sparks?