The radiation oncologist with whom I consulted said the same. I didn't like that idea nor the prospect of months of daily trips to the hospital for radiation. I opted for RALP. Once and Done, so it seems.
I also recommend PT - unfortunately my surgery scheduling was rather sudden, and I didn't have the chance to begin PT prior. Several months of PT mostly cured my incontinence. However a year later I still find then need to wear a "Shield". No big deal.