I'm surprised to learn you lend so little importance to RPRs, Danny.
While I compile and rely much more heavily on my own ratings, I'm always interested in a second (and/or third - Timeform) opinion, to see how much of a difference there is. If there's a huge difference I might investigate further to see if I or they may have missed something.
RPRs strike me as much more reliable since Steve Mason took over. Originally under Dominic Gardiner-Hill (the new chief BHA handicapper) I couldn't agree with his ratings. It wasn't hard to work out his thinking and I couldn't take his work too seriously.
I once subscribed to Timeform (during an enforced extended absence through ill-health from work and needed to pass the time) and found them disastrous. I suspect they have improved a fair bit in the last 30 years, though, and recent sectional analysis appears to be better informing them. But I still like to know how they measure up compared with my own.
It all boils down to 'each to their own', I suppose, and if your own ways work for you then stick with them.
I know I do, but I learned a long time ago that being open to others' ideas is no bad thing.