For travel in the UK on a GWR service. I have to travel fairly long distances by train on GWR every couple of months. Have a railcard so get 1/3 off.
I often do London-Pembroke Dock and London-Penzance. It just so happens that my family have decided they like living at the very end of train lines... Both of these journeys can take around 5 or 6 hours. That's without delays.
If a standard class single was £20 and first class was £40, would you pay the difference? I much prefer travelling in first as I can work, or relax a bit more. But I constantly feel guilty for 'wasting' money.