Powerboost I think depends on how well the engine has been serviced in the first place, if your car has been serviced more than the manufacture recommends meaning some people change there oil every 3000 to 4000 thousand miles when having a high performance engine then I don’t see any need for powerboost I only used it because it was a free sample from the company as they wanted someone to write up an independent report on how well the product worked. Remember we’ve had turbo charged/superchargers and high revving engine for years and we didn’t need additives then as we didn't have them, the fuel you put in your car has over the years has improved, engines burn cleaner now, so tbh I wouldn’t waste your money on it if your servicing is kept up, I think the only people who may gain from it are those who drive around town all the time and never take there car for a good blast down the motorway to clear the crap out from time to time and it just builds up.