Some people are talking about TOO much lift from the 999. I have to disagree.
I bought the ART 999 for Wing-Dinging but only did that once. Then I took it out SUP foiling and I think this foil should be able to handle 20 foot faces. The ART 999 delivers the speed, carry and stability to handle big waves. I have had this out in 4 to 6 foot faces, 5 to 7 feet, 8 to 10, 10 to 12 and then these faces. The foil lets you get up and then go hunting. BUT I am riding a 7' 4" board (which may seem large to people). No way to catch these waves on a 6 foot board.
I credit Sam P'ae in Hawaii with this move: Dropping down the face and it gets too ugly then run off the back of the wave and watch the face until things settle down then jump back over the spine of the wave into the trough again. This started out as a mellow 12 ft wave but turned into a NASTY 15 foot pit.
This was a segment taken from the Surfline Camera at Mavericks. I don't usually surf Mavericks but when I do it's alone.