Any thoughts on shell V MAX which they say is very good but expensive.
Shell V Power max is 99 RON, which contains up to 3 times more detergents and friction enhancers than standard 95 RON E5 & E10 petrol and is similar Texaco Supreme.
It’s made for high compression engines however, the extra cleaning detergents in fuels like V Power, might be beneficial to some injection types but, not direct injection engines which are becoming more popular, because the detergent in the fuel doesn’t pass over the valves, which over time leads carbon buildup and oily sludge can form on the intake valves.
As pointed out and explaned in more detail by @Rene , after you take into consideration higher costs over standard petrol, the difference is negligable, plus all modern cars are designed to run on at least 95 RON E10 and older classics E5.