I did ask my radiation oncologist about Decipher Test. She said that in the cancer center where I will be treated, I have to qualify for it. I'm "not qualified" for Decipher, nevertheless she will see if there's a loophole to have it done for me.
I will start my hormone therapy next week, have an MRI and CT scan, have the markers put in place, then SBRT around the third week of April.
My SBRT prep may be somewhat different than the "pay for service" procedure in the U.S.; our treatments in Canada are tax-dollars-funded.
I will post updates later for purposes of experience- and information-sharing.
It isn't "one size fits all"; each one of us has to choose the treatment that we think is best for us individually.
(I chose SBRT partly because members of my family (including my children-in-law) are more worried, concerned about the side-effects of my initial choice RARP. I saw their point after weeks of research, readings on different treatment options.)