We used the 160 micron bag. LOL, my friend and I were doing this together and got a bit too stoned before we started and weren't paying close enough attention to the color. Just taking turns shaking away. Then, of course, we had to sample it, so got even more stoned. I took a bit and rescreened it through the 73 micron bag and that did clean it up some, but not quite enough.
Clarke recommends 130 microns to capture the largest, ripest resin glands, then 90 for medium and 70 for the small ones and other debris. Unfortunately we don't have anything between the 160 and the 73. I wasn't crazy about using the bags either. I'm thinking of just buying the proper micron screen material, making a frame and doing the more traditional sieve method. I also want to look for a good PC scope. That little hand held one is just too difficult to use.