Raywood, dude - you're spreading bad rumors about the D&M's. The filter on my spike is just as open to the air as yours is. The only place the filter media contacts the chrome spike holder is at the front and rear plates. Where the gaps are (the right arrow), there is a 1/4 inch gap between the filter material and the chrome holder - plenty of room for unrestricted air flow.
If there was such a huge difference in breathability, it must have been something else, like maybe your filter is larger overall, or made from less restrictive material. Peace - out.
There you go catching me putting my foot in my mouth. I shouldn't have answered the question that was posed to me having not had any real experience with the D&M.
Sorry,
Ray