I don't think it will harm but the octane booster isn't going to do anything for you.
As far as cleaners go, most do nothing. I believe people like Techron and I bought a 6pk of it from Costco but I didn't notice a difference after the first treatment. I have 2 more treatments to go. One bottle treats 12 gallons so 2 are needed for the 2nd gen's 21 gallon tank.