2012 autobiography 3.0 sdv6 with ACC on most of the way I normally get 35mpg on a motorway run.

27 -30 about town although I drive like a bit of a grandad.

Anyone out there with a 2015 or 2016 petrol V8 that know there mpg? I'm trying to figure out whether or not 15mpg is a realistic expectation. If not, I'll probably go with the diesel.

May be worth asking over on FullFatRR; you'll find more 5.0 chaps there, and L405 MPG figures would be pretty comparable with the L494.  Visiting from DISCO3.CO.UK
2006 Discovery 3 TDV6 Auto HSE Zambezi Silver

14-15 mainly round town. Up to 23 on a gentle 56mph run. Evoque HSE Dynamic
5.0 Charger MY12

On board computer when I look says 32.1 mpg, but I normally get around 461 miles to the tank full, which I believe differs.
In Germany I managed to get it as low as 14 mpg showing at just over 120mph indicated, but great fun.
In winter with FBH on I get around 20mpg around town using paddles or 18mpg if left as auto. 78mph = 30mpg.
All figures from computer except miles per tank plus mileage log for when used for business. John

RRS MY12 SDV6 HSE. Sumatra Black/Ebony & Walnut + Dynamic Pack, + Cold Climate Pack + Memory Pack, Digital TV/DVD, Premium Leather, Cornering Lights, Cooler/Fridge Box, & most Options.

3.0 Sdv6 2012, about 25mpg, mostly town driving with 10 mile 70mph round trip daily. 2015 RRS AB SDV6, Fuji White, Ivory
2012 RRS HSE SDV6, Sumatra Black and Ivory
Audi A5, 3.0 TDI, Gone
Audi TT, 3.2 V6, Gone
BMW 5 series tourer, Gone