All treatments have improved greatly, and there are so many variables that it's not logically possible to compare the treatment outcomes. Several options can provide similar results so it often comes down to personal preference and consideration of the side effects as you mentioned.
The potential for bowel side issues can be a considerationwith with radiation, which would be more of an issue for anyone with previous bowel problems.
The main variable and most important consideration is selection of the best doctor available, who will have a big influence on the outcome. Robotic techniques are being improved, so I'd want a top surgeon with lots of Robotic experience and also extensive experience with nerve sparing open surgery, as it occasionally becomes necessary for the surgeon to revert to open surgery.
Only 2% of one core is a tiny amount of cancer. Biopsy reading is subjective, and what lools like cancer to one person can appear normal to another. A 2nd reading should be obtained from an expert pathologis if you havn't already done so.
With recent more extensive screening, most men are now diagnosed with early stage G6 cancers, in some cases with very small cancers, which raises the dilemma of over-diagnosis and over-treatment.
Active surveillance is usually discussed for men who meet certain criteria: there are a number of publications on it, including several by John Hopkins on Insignificant Cancer. www.urology.jhu.edu/newsletter (winter 2003 newsletter).