Sportiva mantra sizing compared to solutions and futura.

Looking at the sportiva mantra shoes and curious on sizing both based on fit and stretch.

I’m a size 41 in solutions and 40.5 in futuras. I’m a narrow foot so can size down comfortably in narrow shoes like the futuras for some reason  

mantras are wider so my gut says size them ok 41 like solutions unless the mantras stretch a ton. 

I don't have solution. I'm wearing 40.5  in mantra, 40 in futura
And per this LS official video, you should have your mantra 1 FULL SIZE smaller than solution. youtube.com/watch?v=ebyB9g9…

I wear 39.5 in Solutions and the same size in the Mantra. Both are a snug, performance fit.