Pipes: I don't pack quite that much, but (as you might guess from my messages), I'm a HUGE fan of connecting the mouthpiece directly to the Evo core, while covering it with the modified delrin insulating sleeve. The problem I found with a really tightly packed load was that it required hernia level suction to work at all. I have noticed that different strains of herb work better with different packing levels. My experience is that the more moist/sticky/dense strains work better with a lighter pack, and the drier strains work fine with a heavier pack. I also noticed that a fine grind really requires a light pack, and a finger crumbled load can be packed a bit more with no hernia.
I've always used an extended length delrin mouthpiece when connecting directly to the core, and the past week or so, I've been using the same mouthpiece with a UFO in the end; I'm finding that I don't have to vary the load amount and packing amount anymore. As I mentioned in an earlier message, the UFO serves to also pack the load down a little, since it extends quite a ways into the core. I generally load the core fully, tapping the base of the TV at 25% full, 50% full, 75% full, and then at 100% full. When I insert the UFO mouthpiece, it packs the load down, probably to about 75%. This method has worked great for me, regardless of strain.
I'll post a picture or two tomorrow of my setup, as requested last week while I was on the road without my TV.