If the manual says 87 octane (or higher), that is all you need to run, 87 octane gas. The engine is designed to run at that octane rating optimally. You can run higher octane gasoline, but all you are doing is spending money you don't need to spend. My daughters Acura TL requires 93 octane fuel and running less impacts performance and can ping. My Ecoboost twin turbo is designed for 87 octane fuel and runs perfect all day long as it was designed to run on 87 Octane. Towing a camper makes no difference as the computer compensates. Higher octane for towing would help but isn't necessary ass the computer compensates for the octane fuel used. You can go higher, but shouldn't go lower than the minimum required.
Sunoco used to have a pump with five grades of fuel years ago all the way down to 85 octane (could blend 85, 87, 89, 91 and 93 at the pump). Sunoco 85 Octane would be used only for low compression engines or at the time, people trying to save some money as it was the least expensive fuel then.
Use a good grade 87 octane fuel and save your money.