I haven't gotten any Isoplast yet,but the Tomahawk stuff that can be had here is probably a tougher,and overall just flat-out better,esp if you are talking about the short,thin-walled ferrules.
I have seen OLD Predator's that had practically 1 inch ferrules. In the case of those,I am confident the Tomahawk would be a superior material there too.
I am only basing this on the quality of the material itself,such as resistance to chalk,durability,and availability,not it's effect on playability. Tommy D.