In reply to BRILLBRUM: the racing flat is pretty dead now as its not the fastest shoe for the elite, and certainly not for the average runner. I've done plenty of races in flats, and if you got tired and your form deteriorated then flats really didn't help. I know my times improved when I went to a more cushioned racing shoes, at the expense maybe of my finishing kick.
Ultra low stack fell shoes have a place but for cross country, spikes, for longer races, more stack, for the same reason as for road races
It's a little tiresome to look at the shoes and wonder as I never ran what I would consider a good marathon ...and I think my style and energy efficiency would have benefited greatly.