I have had all the full upgrades (100% Appliances, 100% Food + 100% Decor) in BigBayBurgers & PizzaPaisan.
Usually I used all 3 boosters during the duel challenges (RushHour + Cheers + FastFeet = BBB &
RushHour + TastingSpoon + FastFeet = PP).
End up still lose to those duel don't know is real player or not whom can scored >2k duel points (with all the same 3 boosters used in same venue like mine). Initially I started doubt on my playing skill, but no matter how I tried the most can hit up to 1.6k duel points only in BBB/ PP.
Your input would be much appreciated. Thanks.