Personally, I think the way you choose the right shoes is rather straightforward. The shoes do not make any difference, but legs and feet do. The Primiero Dolomiti Marathon track could well be classified as a trail running race, so many people might think that trail running shoes are obviously the choice. However, I believe that the course is fairly linear to allow the runners to use the shoes which fit best for training on the asphalt. Since few segments of the course develops along gravel roads and mule-tracks, if I may give an advice to those people who are a little bit sensitive on their foot soles, the use of well cushioned shoes is suggested, so the ground impact can be deadened. The stretch of the route from Lago di Calaita leading to Passo Gobbera (shared by the 26km and the marathon) develops along a small path in the forest, facing low vegetation and mixed ground, so I also recommend shoes with a fairly strong upper, together with a pair of high socks. In the event of bad weather, no shoe can really save you; the ground would be anyway slippery and wet in some places and there is nothing a outer sole can do about it.