world's end was a bit of a miss really, it's watchable but it's really nowhere near the perfectly paced classics of Shaun of the dead and hot fuzz. It doesn't have that same grounded humour and the writing seems weaker.

I think they tried to do too much in world's end and the antagonists also came across like a poor rehash of hot fuzz but with generic aliens instead of eccentric villagers. It doesn't click very well and lack's it's own personality. None of the characters are even that likeable really.

I also don't think Pegg and Frost worked so well in the flipped positions, as a result the dynamic is kind of lost between them because Frost is trying to play a more mature / serious character compared to Simon Pegg. Something that is not an issue in "paul" where the character dynamic remains the same as Shaun of the dead and Hot Fuzz.

I don't think it helped either that "world's end" was a bit too close to "this is the end" which came out around the same time, the latter generally did the apocalypse comedy a lot better imo.

Paul also had one of those comic-art tin collector's cases which went along nicely with the Shaun/Fuzz ones.