I haven't done the CPL yet, but some comments re. the A4 kneeboard from a PPL's point of view:
I'd have thought it would depend very much on the individual. When I was doing my PPL, my instructor always showed me a variety of techniques and tools, and suggested I choose whichever I thought was best.
I opted for an A5 kneeboard. I also discovered that most of the plog sheets which were available didn't fold up to A5 size and show me all the information I needed in flight - so I designed my own, with all the details I needed during flight planning (true track, true heading, etc.) on the "reverse" side, and all the details I needed during flight (magnetic heading, leg time, etc) on the "front". This has served me very well during 200 hours of flying - I've used it for cross-countries ranging from 20nm to 400nm, and even adapted it for local flights in controlled airspace where I've wanted somewhere to note down frequencies, squawks, and other instructions.
During my PPL training, my instructor was away for one of my cross-country lessons, so I flew with a different instructor. This instructor was very unhappy about me using my "non-standard" plog, and insisted I use an A4 kneeboard (he lent me one), and a standard piece of paper. I had no problems with the plog itself, but I simply did not like the A4 kneeboard. I found it got in the way of the yoke, my elbow banged it when I moved my hand around, and I felt uncomfortable with something that big on my knee. Fortunately, my regular instructor told me to ignore the crap that this guy told me - that I was perfectly ok to use an A5 kneeboard if that's what I found easiest.
I'm not for one second suggesting that you should use an A5 kneeboard - only demonstrating that everyone's different. Whatever you've used in the past, if you liked it, you should continue to use it. And if you didn't like it, then try out some alternatives. I don't see why the CPL should be any different in that respect.
Good luck!
FFF
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