Good points, and apologies if you thought I was being harsh - it was not intended.
From my point of view, for those who don't have their own photos, or the means to obtain them, then using 'archive' material is OK, if it means they are able to participate.
However, this could possibly lead to some very obscure, or rare, specimens being presented by those who do have their own material, by those individuals also using 'archive' material. This, in essence, is contrary to Gary's guidelines when setting up this 'quiz', and so I believe it is only fair for Gary to make the ultimate decision.
Regarding identifying the aircraft, personally I have only used experience or a guess (so far!), without consulting any references, but I guess that's personal choice.