I am glad this came up as I had exactly the same situation as bcfc about a year ago, I was getting conflicting advice from different instructors at different clubs when I checked out on different or similar aeroplanes. I later called the CAA and was told the following:
1. Your Logbook is your own personal record.
2. P1/s is ONLY for a flight test with an Examiner, Eg for your PPL, IR, Twin Rating etc. You total these hours as SOLO.
3. If, when you have a PPL, you fly with an Instructor on a check-out, if he is TRAINING you on a new aeroplane type, ie he demonstrates something to you and touches the controls etc. Then you are PUT and the hours are DUAL.
4. If, when you have a PPL, you have flown this aeroplane type before and YOU are demonstrating to the instructor you can fly the aeroplane OK, ie he does NOT touch the controls during the flight, then you log the flight as P1 for yourself.
The guy I spoke to at the CAA said himself that this is a grey area and summed up by saying only one person can log the flight as P1, but alot of pilots are cheating themselves out of P1 hours.
I would be interested in what you all have to say about this advice, especially considering the conflicting posts above.
Regards SD