One thing to clarify with the urologist before you decide is whether the prostatectomy would be nerve sparing on one or both sides, or non nerve sparing. You should also see an oncologist to talk about the radiotherapy, how long you would be on the hormones, and whether you might be suitable for brachytherapy instead.
All things being equal, surgery and radiotherapy have almost identical success rates in terms of remission at 5 and 10 years but are quite different for side effects - side effects of surgery are immediate but hopefully improve with time while side effects of RT tend to develop years later.