I notice more pops and bangs on Tesco's 99RON too but tend to use Shell V-Power mostly (probably just psychological but I like the fact that Shell have the extra engine cleaning additives in their fuel)
Our local shell station changed hands a few months ago and is now a BP station. Since then I have been using Ultimate. The car seems to prefer this to V-Power. The engine seems smoother and there is no appreciable difference in performance.