I went with the ninja down approx 8 miles of the Manistee river for my first ever packraft trip and the paddle worked *much* better than anticipated considering the small surface area of the blades. The river speed was relatively high considering all the rain we've been getting out here in Michigan over the last couple weeks.
It is definitely a 4 piece, with a simple metal pin connection between each piece. The pieces fit very snug and the paddle feels quite rigid. I was very skeptical that I would have much control, but at around 210lbs with ~15lbs of pack gear, my Yak handled great down some pretty quick moving class 1 water. There were instances where I needed to maneuver around some fallen trees, and I felt very under control. The blades are nicely shaped for normal paddling and give decent propulsion, but aren't the best under backpaddle (of course you could flip the paddle). The paddle weighs in around 14 oz on my scale, and the center pole could probably double as a shelter support.
I can't comment on how this compares with other paddles, mainly because this was the first time on a packraft, which seems to have such different dynamics compared to a kayak.