The problem, DD, is that there are functions on the CRP-5 that are not available on the CRP-1. Compressibility calculations, for CAS/TAS above 300 kts TAS and fuel weight/volume convertions for various specific gravities as examples. Both are possible by formulas and electronic calculator, but the CRP-5 is quicker, simpler, requires less learning and will get the same answer - remember the JAA answers are calculated on a CRP-5.
The CRP-5 is a Pooley's product, so I doubt that the paper examples are CRP-5s. They are most likely generic flight computers. I would stick to the real thing - it is expensive, but I have 4 good flight computers (2 RN-issue of different sizes, Jeppeson aluminium and a CRP-5) and the CRP-5 really is the best.
Good luck.