The tests start when you're 60 sara4, and arrive through the post a couple of days after the birthday cards. I did mine, as we have a family history of bowel cancer, and a very good friend has been in treatment for that for over 7 years. 3 years ago, one of her regular scans confirmed it had wandered into her liver. More chemo, more surgery, but she's 3 years clear, at 62.
I've just had my 2nd test as part of my 65th birthday celebrations (no name change for me though). I have also had kidney tests as a result of concerns on a recent (monthly) blood test. Last week, I had the mammogram screening, which frankly I find more unpleasant than the poo collection. So, I'm grateful for the monitoring.