I had a 2015 Ford Focus 1.5TDCi which I owned myself. I put 66k on it using only BP Ultimate or Shell V-Power diesel, I nursed it from day one and never really gave it a hard time. It spent most of its life with me at 70mph with cruise control on. I even moved from the OEM 5w30 WSS-M2C913D oil and started using an ACEA C3 oil for blthe higher HTHS and less SAPS to clog the DPF and inlet manifold and run 5k OCIs
The car was forever having issues, stuttering, hesitation and dumping diesel into the oil.
I now have a company car. A 2016 Ford Focus 1.5TDCi which gets serviced every 12.5k, gets run on supermarket diesel and I beat the life out of the poor thing. It's quieter, faster and so far has been much more reliable!