Best material for poncho tarp

I would go with silnylon unless you feel confident that where you are taking it has open trails and wont be thrashing against vegitation much. The Cuben also comes in 4' widths while silnylon comes in 5'.
Cuben is awsome for a tarp material but is not nearly as durable as silnylon in terms of abrasion.
MLD's site sell both versions.

While I'm not a material pro, rockywoods fabric sells cuben in 54" widths. I oredered some but am yet to receive it. It also states a weight of 0.253 oz/yard^2. I guess we'll see how accurate that is when I get it…you could bring 2 tarps at that weight! :)
FWIW, my poncho/tarp is silnylon…

*just realized you specified 0.6 oz..nevermind then. :o

0.253oz/yd^2! Blimey, that *is* light. I wonder if it could be laminated with mylar space blanket to make a light heat reflective but rip resistant cloth. What sort of spray or brush on adhesive would work for bonding them I wonder???

I find myself thrashing through brush about once a day on hikes… However, I am rarely wearing rain gear as I do this. I guess then that brush is the main issue; Francis Tapon successfully used an MLD cuben tarp for his CDT yo-yo, but not as a poncho.

Difficult choice…

Go silnylon on one half and cuben on the other half.

That way you can wear silnylon on the 'front' of the poncho which will make it more abrasion resistant, but have cuben to save weight on the back half.
It will also allow a poncho tarp with a catanery cut (if you swing that way).

Ok i'm joking…
Actually i'm 'half' joking.