;-)
I was going to say - I rather liked the illustrations in the old Collins HFP! What does that now make of your post #5 above and the 5 people who 'liked' it, given it was total misinformation lol?!?!
I don't recall the Hamlyn especially ...
Another difference not mentioned on this thread was the Shell Guide was Britain and Ireland (?), whereas the HFP was Britain and Europe plus Northern Africa and the Middle East, so maybe not directly comparable. The HFP came out 8 or 9 years before the Shell Guide I believe. HFP did have very European rare vagrants/accidentals in the back listed, but only illustrated some, and other 'commoner' European rarities in the body of the text such as Forster's Tern etc and eg a double page spread of some of the more regular Yank passerines.
Someone showed me the Shell Guide (early 90s) saying that was the book I should have, but I was just that put off by the faded little pictures that I didn't delve further (I wasn't a UK twitcher per se, so had no major interest that the Collins didn't provide tbh).
As mentioned, I did rather like the illustrations - some pages had a background colour other than white iirc, and I did like the occasional vignettes of some of the birds (perhaps desert sparrows or Bedouin in the background of one of the desert raptors??)
My HFP is in a box somewhere (plus the Shell Guide and a few others I picked up like the Lars and Mitchell Beazely also second hand out of interest)
Some images from inside are here -
The Birds of Britain and Europe With North Africa and The Middle East by Hermann Heinzel, Richard Fitter and John Parslow Collins, 1972, colour illustrations throughout, paperback Very Good Condition, some edge and shelf wear, some rubbing, bumping, creasing and soiling to edges and corners...
www.morgansrarebooks.com
I don't think they're bad. And we are of course not talking the level of descriptive text as in the current Collins by any means (the book is now c45 years old). Apologies to the OP if the discussion isn't about the Shell Guide as such.
EDIT: Oh and an interesting challenge trying to tick off 'whole pages' of the HFP Collins - usually in a European context, made trickier as some pages often included one or more much more difficult/impossibles like Andalusian Hemipode etc