I use a 1,600psi Ryobi and most typically a 20 degree tip. It's perfect in my experience. It has good cleaning power and you can get up to a couple inches away from the clearcoat without worry of damage. I also use a MTM Hydro foam canon with it which I fill with a dilution of Meguiar's D111.
2006 S2000 - Berlina Black - PU 10w30, PCX-004
2017 340i xDrive - Black Sapphire - Dlr Fill, 114...898
2019 X5 xDrive 40i - Mineral White - Dlr Fill, 114...898