I've been looking to either buy a windshirt or driclime windshirt. In order to test the fabric/sizing, I ordered a L and XL Marmot Driclime Jacket.
In the past, I've read horrible things about Marmot putting essentially a vapor barrier fabric on these kits. Some thought it was silicon-coated nylon last year. Needless to say, at least one past model of these jackets did not breathe well or at all.
I called and inquired about the fabric on this year's models: Banshee P-170. After explaining that last year's model did not breathe, I was told "it did breathe, but this updated fabric should breathe a little better." It's a polyester face, and I confirmed no coating of any sort other than a DWR.
The jackets were just delivered. When doing the informal blow and suck test on the fabric, I couldn't really blow any air through, but did barely feel the warmth on the other side of my breath. I could not suck through the fabric.
[EDIT: There are small side panels near the pockets. When I blow hard through these, I can–very slightly–feel the moving air. I took a can of compressed Co2 and shot it at the fabric: the small side panel does allow you to feel the air, but again, just barely. I could not feel any Co2 coming through the front. In comparison, I have an Arcteryx Gamma SV with Powershield rated at around 6 CFM. I can breathe/suck/shoot Co2 through it and feel it. I'd guess this Windshirt has a CFM of less than 3, probably 1 or 2. My best guess it that the fabric is coated with something that will greatly inhibit breathability]
Are the driclime jacket/windshirt, as well as the Ion still off-limits for a breathable windshirt? I understand the test is unscientific and really only tests air permeability, but in the past it has been a good indicator of breathability.
An interesting note: I have found some websites to list last year's model as "Banshee Nylon." This year's is Banshee Polyester. Perhaps Banshee is coating/laminating/sealing their fabrics?
