I too was at the Sheffield screening last night.
I thought lifecycles looked beautiful, and benefited from having an attempt at a narrative- it might be corny the old guff about the life of the bike and how it all returns to the earth etc, but it gave the film some sort of a story.The bits of narration helped with the "story line" too.
I liked the section where a bike was stripped and re-built, but then maybe that's just me!
I thought some of the visual techniques were repeated a bit too much- the scenery changing colour from green to gold etc. I was a bit bored by that.
The riding clearly was awesome, dude. You have to admire the technical ability of the riders, and the film makers for capturing it so well.
I left thinking that it just wasn't really an original enough idea.
Pleased to have seen it on a big screen though, colours and detail all superb.
Vast on the other hand seemed to be some fairly average riding in stunning locations.
It did make me want to go and ride though- because it looked like the sort of riding I might be able to do.
I guess it depends what you want from a film, something to look at and go "wow", or something that makes you think- "that looks like fun, I think I'll have a go"