If you're planning to summit mont blanc I'd imagine that insulated boots would be recommended? It can get pretty chilly at 4000m, even in summer! You don't wanna lose a few toes if you end up spending a night out in a storm.

Have a look at needlesports website, they give a good honest low-down on what the capabilities of boots are. Their estimation of the Trango S Evo is that its suitable for summer scrambling and via ferrata. I have no experience of either boot to offer, but I plan to wear my insulated scarpa freney gtx boots when I go to the alps next year, not my mantas.