Can't help you at all with Vortex Dream Mat but can with recovery to 300 mesh free milling non sulfide. Spent almost 4 decades on this and still at it. The matting I'm using now is the black Vortex material and similar products like Martin found on Ebay. The trick is classification. For this matting 30 mesh is as large as you should go to recover properly. 20 mesh will hang and stick in matting slots rather tightly and ultra fines will simply slide over occupied space and its gone. If you have larger gold in your mix, run it by itself another way. Its worth the hassle. Pitch of 1' per foot still works but never feed material so fast you loose sight of mat or its gone again. Water flow is more a call based on my last sentence. I frequently check all waste on my 8 ft shaker table that I pulled off 300 mesh for years and if you are even close to doing it right you will be impressed. I've added the light Keene sluice screen to some of my tests and the gold will deposit in the mat differently. Yield is the same. Otherwise I never use a riffle system for that fine of gold. If I can get it to lay down I give it nothing to bring it up. Micro gold recovery is just different from what most people do or want. Getting it in a vial super clean is unique too but not a big deal. Hope that helps some.