If the clo thing interests you, here is a table I found. A couple of salient points. First, the best synthetic is Primaloft Gold (unless something newer is out), note it falls in about equal to 600-650 down. Most of the other Primaloft equates to 550 down. Second, I'd not due a down less than 800 over a good Primaloft puffy. The 550 might be lightweight but lacks anything if it gets wet.
Why is Primaloft Gold the best synthetic? How does it compare to Polartec Alpha?
