Which of these E Class would you buy for reliability?

[Big Rig]

And least bork factor. Do any of them have large known problems I should be cautious of? We have about 12k to spend.

All from the same dealer as he's only 80 miles away and he's got a great rep amongst the merc community I've read.

2012 E350 £9,490...

https://www.mercland.com/vehicle/mercedes-e350-in-...

2015 E350 £12,990...

https://www.mercland.com/vehicle/mercedes-e350-in-...

2015 E220 £12,390...

https://www.mercland.com/vehicle/mercedes-e220-in-...

2015 E250 £9,490...

https://www.mercland.com/vehicle/mercedes-e250-in-...

[TarquinMX5]

I haven't looked at any of the vehicles listed, however, I would just make one comment: one of the most common issues I see raised on MB Club forum is problems with the Adblue system (ie BlueTec diesels, not the earlier BlueEfficiency cars).

As it doesn't apply to me I haven't done any research but my gut feeling, and it's no more than that, is that it crops up more on the 4-cyl cars but that might be because they're more common than the 6-cyls. Again, personal preference, the 6-cyl is much smoother than the 4-cyl and not much less economical. The revised 265bhp 350 diesels (straight drls before the facelift) had the later 7g+ gearbox. However, with c10-year old cars, much will depend on how it's been treated, serviced and driven.

[Scrump]

The early E350 is Eu5 so if ULEZ and CAZ areas are important to you then avoid that car.
Conversely the later E350 is EU6 but has adblue, which can throw up a few problems.

I don’t know much about the 220:and 250 models as I discounted them very quickly after some test drives.

(I have a facelift 2014 E350, had it for 7 years and still find it a great family and long distance cruiser).