My father had surgery for prostate cancer at a young age, not as young as I, and did very well, both from an continence and ED perspective. Of course, it helped that he had Dr. Patrick Walsh as a surgeon. Certainly, my father's experience and Dr. Walsh's bias toward surgery influenced my decision to have robotic prostatectomy. My age, health and choice of a top-quality surgeon gave me confidence that the chance of side-effects would be made as small as possible.
Another factor to consider is how you will personally deal with post-procedure PSA tests. For me, I felt that I would do much better psychologically with the greater "finality" of surgery, including both the final pathology report and the PSA level that (hopefully) goes to an undetectable level. Waiting for that first post-surgery PSA test was still rough, and I'm sure my anxiety will increase before a number of subsequent tests. However, my hope is that a sense of being "cured" will come sooner than had I waited through a slower decline in PSA that a radiation route apparently takes.
Father diagnosed and cured at age 52.
08/21/07: Diagnosed with T1c cancer
1 of 12 biopsy cores positive; 10% tissue
Gleason score: 3+3=6
PSA level prior to biopsy: 4.3 (velocity < 0.4ng/ml)
10/19/07: da Vinci prostatectomy by Dr. Vipul Patel at OSUMC.
Difficult surgery due to prostate inflammation.
Both nerve bundles spared.
Spongy erections began within 24hrs of surgery!
10/24/07: Catheter out; down to 1 Serenity pad/day next day.
Final pathology: neg margins, no capsular penetration,
Gleason 3+3=6, 5% tumor involvement, multi-focal.
11/04/07 First usable erection with Cialis
11/22/07 Thanksgiving - Bye-bye, pads
01/17/08 First post-surgery PSA result: < 0.008 ng/ml