Hi Great Dane,
Some random thoughts....Having just gotten back from the camino, I would say take the one that dries the fastest and is the most durable. Although some people manage to look pretty pulled together on the camino, how things look quickly becomes less and less important and functionality rules when it comes to what you want to carry and use. Much as I love silk, one of the problems with it is that the fabric runs forever when it's washed so you have to be careful.
Another consideration is whether you want to be able to use it when you get back. My experience especially from long caminos, is that few things come home in decent shape. I always take clothes and things that are old and expect that things may be useless by the time I get back. That was certainly the case on my most recent camino which was almost 3 months. Everything will go in the ragbag (except my towel/sarong)
I took a light cotton, not quite voile one, which I made myself. It served as a towel, sarong and a 'light blocker' in albergues. I often hung it down the side of my bed when the lights were bright and shone in my eyes when I was ready to sleep. It wasn't a great towel - but then after terry cloth nothing is. It dried fast, it was light - just a few ounces- and was bright and cheery. I liked it and it's still usable.
Buen camino!