Humans love novelty (protons), so do I, but don't dismiss photon technology which has 20 years of refinement in planning and delivery.
I took my rad onc's advice based on his experience with thousands of prostate cancer cases and had 28x IMRT/VMAT on a Varian Truebeam LINAC with spacer and markers. I'm two weeks post radiation. Mild urinary symptoms.

FORTY Ounces of bladder prep, you say? Shoot, for me
it was 16 oz. That's medieval
Age 70 4+3 local