At only 3.5g each they are certainly light, but I have issues regarding their durability. Every time I have used them I have had at least one fail.
Admittedly on one occasion it was as a result of banging them into frozen ground using the hammer of my ice axe which is obviously outside of their intended performance envelope (I shredded 4 out of 8).
More worryingly however is that at least two have failed due to manufacturing faults during normal usage.
I’ve since decided that the slight weight advantage over titanium stakes is negated by the need to carry several spares to cover breakages.