MP Megatron is by far the most frustratingly difficult Transformer to transform!! Graaargh!

I don't agree with RiD Side Burn... that toy's not hard at all. BT Smokescreen... well, all the BTs/ALTs (and Alternities) are tricky to transform, that's just the nature of these toys if you want highly realistic scale car modes and articulated robots - but by BT standards Smokescreen's pretty intuitive. I do agree with Grimlock (and thus Wheeljack) though... that design is counter-intuitive and I don't find it fun. I agree with ROTF Optimus Prime too -- that toy is very complicated to transform, and those two red bits under the front windscreen parts are a pain to lock in properly in truck mode. The DOTM Jetwing Optimus Prime retool has significantly reduced those parts and as such that toy is MUCH easier to transform than ROTF Leader OP! It's amazing what one little modification can do to make a transformation easier and more fun.

Big Convoy is also a pain in the butt to transform... a lot of effort to transform him into a rather underwhelming beast mode IMO. He's the king of shellformers. By G1 standards, I'd rate Darkwing as one of the less intuitive ones to transform, because part of the transformation is rather unsymmetrical. 1984 Jazz and Megatron were the trickiest of the first year TFs for me as a kid (not that I owned either toy, but I knew other kids who did). Darth Vader/Death Star is also cumbersome (another great shellformer).