I am using this specific felt for my loads as it came highly recommended from some waterfowl hunters.
http://www.durofelt.com/image_75.html
Though I would probably order some thinner rolls as well depending on what load you decide to roll so you can try different combos to get your perfect wad column height. For me using the Winchester hulls and Bluedot three 1/4" wads and a 1/8" nitro card gives me the exact height for roll crimping 2 1/4oz loads.
With felt or fiber wads and roll crimping you can make all sorts of adjustments to how you load. I was just thinking how I could probably make a cold weather specific load but It doesnt really get all that cold down here.
I came up with a idea for a die to remake the skirted gas seals Winchester used in their 8 ga shells but I dont really see a need for them.