In reply to climb41:
Not really, apart from trying them on in a shop. They only had half a size too small for me, otherwise I would have bought them (can't remember which model) since they clearly had the wide toe box that I want. I see people on Strava who run big miles and ascent in them on dryish terrain (Colorado) and seem to swear by them.
Instead, I bought a pair of Topo TerraVenture which had a very similar feel.
They have been great, apart from, and this would be my issue with Altras or any pair of shoes that cost over £100, that the uppers have started to shred after doing barely 200 miles on pretty benign terrain. is this normal? (For me, it is - I had the same experience with 3 pairs of Mizuno Wave whatever.). I have bought Shoe Goo to try and stem the decay, but, but, can't the shoe people strengthen the uppers a bit?