I've worn La Sportiva boots for about 5 years now. Not that particular boot, but similar. Trango Prime and Trango GTX. These boots fit like a glove, need no break-in, and are super light. They are not super durable, and there are narrow, so you definitely don't want a wide foot.
Sizing is rather tight, possibly because of the narrow cut. I usually wear a US 11 max, and in their boot size I need a European 45, which is usually translated as 11.5, but even with thinner socks, that's not working for me. They don't stretch out over time, so they have to fit from day 1 or you won't be happy.
My kids wear Trango GTS as well, and both love them. Never had a blister in any of them.
The Trango Prime is warm enough for Whitney in winter, but it isn't very waterproof unless you gunk it up with serious amounts of SnoSeal. I hear better things about the heavier Nepal Evo GTX, but it also weighs in much heavier.
No experience with the Asolo boots.
