Hi,
I have had the 5 day version of RT. I started with a diagnosis not too dissimilar to yours, though I had a starting PSA of 17, and a T2b/c diagnosis.
I had opted for RT as the primary treatment. ( The uncertainty around the T2b/c edge conditions was one- but not the only- factor in choosing RT). It would have been the standard 20 day job, but the radio team was unable to get a consistently clean shot at the target, so I switched to the Top Gun, 5 day, MRI guided machine.
The treatment was a breeze. There were only a couple of days afterwards when I didn't stray too far from a loo . But that was it.
Has it worked? All you can ever say is : so far so good. I am 2 and a half years post treatment, with a still negligible PSA, so it's : so far so good. Would I do it again? Yes.
As you will have discovered from the many posts on here, there is no 'right' choice to your treatment options. The things that matter are that you do the research, listen to the professionals and then pick the one you can be most at peace with. The path is as much emotional as it is medical....
Best of luck