Hi Francis, good article and thank you for sharing it. I haven't really used an umbrella yet on any hikes per se, but i did use an umbrella at last years Burning Man, and it was nice to have that shade. Since it was a week of living mostly out of a backpack, and walking around A LOT, it was kind of like a backpacking trip.
Handled some fairly strong winds too at times. Would have been nice if it was a reflective type.
The Senz umbrellas look very interesting.