Guess it really depends, if i’m doing a long journey, i’ll fill it up, so i know i have enough to get back home as locally the fuel is cheaper than most other places i goto on a regular basis. so makes sence right.
Then the rest of the time i’ll run it till its empty sometimes till it says 0 miles then put £20 in, basically becoz around town / stop start you carrying extra fuel and my car is just faster away from a stop when it’s just me in it not the whole family. Same with a full tank. guess thats why hot lap times get set with less fuel..
I also think modern cars having fuel injection, a full tank of juice for pressure is not needed like i think it was with older cars seemed to get better mpg with over half a tank and never had any problems with anything fuel related or ran out of fuel.
So far on the scheme every vehicle has been a diesel, This time i going petrol, just placed my order last week. That’ll be better around town but worse on a long journey than a diesel but again it’s driving style as well as other factors as to what works best for you and need to be taken into account.
So no way is wrong imo.
Sometimes we limited in our choices as to the engine in certain trims etc that meet your overall needs. it’s a trade off.