I'll check the flatness of my '88 leaflet when I'm home. (Although I'm sure I corrected Darkwing/Dreadwind names mix up!). I also have bad photocopies of the 1994 and 1995 booklets but am sure they were intended more for retailers than customers as they also list the product codes.
Also, there was another earlier 1984 UK leaflet with only he first six Autobot cars and no Megatron. I have this somewhere too.
Edit: Actually, I see now this is on Botch's site too.
I remember looking at that for hours. Mine has blutack marks in the corners where it was pinned to the wall. I think Combiner Wars has made it clear to me that the Special Teams are the pinnacle of Transformer gimmicks. I can't think of anything more fun.
I still have mine in a box somewhere though it is ragged from wall use back in the day and marked where blu-tac stuck to it and would not come off without a fight. Has some tears but I can't part with it.
These aren't rare, but I haven't seen them linked here - I can scan properly if needed. Just the first few robot points offers.
I was going through my catalogues. I have nothing to add, but this page did inform me that I have a US 84 one, which I didn't realise I had. And also an American glow in the dark poster with a chance to win a go kart styled like Hot Rod!