I've been using the pyramid tea bag for a few days now in my 510 and it does seem to work quite well. I am doing it the way that GrimmGreen showed on one of his videos. Basically roll it up, fold in half, cut to length, then make a few cuts vertically to sort of fray the business end. I think this is makes a better filler material than the polyfill. I remember Chris and a few others noting that the 510 seems to like to have a cart on it to get good flavor. If you just drip with not cart filler, there is a bit of a metallic taste from the atomizer. I tend to mainly drip but do use the cart where I put one drop on the cart, two on the atomizer (though I start with a good moist cart). That way you get good vapor, good flavor, and if you don't keep the cart too full, you avoid getting juice in your mouth which basically sucks.
What I like about this filler material is that you don't get the burnt polyfill taste and it seems to wick much better and more consistently. Now if the atomizer/cart is getting dry, I just get a bit of the metallic atomizer taste and then I just re-drip using the 1:2. It's really easy to do and just plain works. Plus the tea isn't half bad.
Shane