Got the 190 TSI on a 21 plate (R-line).
On a decent run (in my case 100+ on mostly motorways), adaptive cruise set to 70, driving mode dynamic - good podcast on the entertainment system and just go with the flow (means average MPH over this distance comes back 52/55 MPH) - see around 50mpg typically.
On a recent trip I saw 59 (140 miles avg speed 52) - slipstreaming lorries just to see what sort of mileage I could achieve.
Figures are based on the cars trip computer so not sure how accurate - previous car was an A4 with basically same drive chain and predictive adaptive cruise and got similar figures.
On B roads over shorter distances I can still get 40ish - but again using the (predictive) adaptive cruise as much as possible and keeping my right foot off the gas.
Didn't; fancy the 1.5 - it's a big car and felt it needed the bigger engine (although I didn't test the 1.5 so this is just an assumption on my part)
Hope this helps