Switching to OCP

Moin, after our annual driving performance has not developed as expected and the thickness has proved to be relatively vulnerable (many small things, turbocharger damage via car warranty, …), I seriously think about an exchange 3.0 CDTI for OPC. The driving fun will be a bit (hush) higher, insurance is at about the same level, the fuel consumption is expected to run out in about 8.5 to 11l. The tax is drastically lower, this is likely to be a part of the extra consumption as well as against my first assumption, can I not continue to use the winter tyres, because of the even larger braking system?! Gas conversion would also be a possibility. Opinions, tips, hints or ideas? Greetings, Thomas