The Simpson 15" Surface Cleaner rated to 3400 PSI was designed to work with your pressure washer; since your pressure is near the top of the rating you would get good performance from it.
Your pressure washer at 2.8 GPM doesn't deliver enough water volume to drive either of the 16" surface cleaners we sell. The Specs tabs show the BE unit needs at least 3.5 GPM to operate properly, and the Eagle unit needs 4 GPM minimum.