I bought one a few years ago, crazy me, tried to ski down the rope to my best pass. Definitely take the dowels out. I went out the front at 35 going faster than I have ever been on a ski after the line lock. If I had hit the 2nd wake going that speed I may have never skied again. My wife said I ended up about 10 feet in the air and did two complete rotations before I hit (almost to the next buoy by that point). Wish I had a video! Scared me so bad I never used it again until last year. It was completely my fault thinking I could ski in pb territory without figuring out how to use it. I am also getting age challenged. Last year I pulled the triceps off my elbow very early in the season, which ended with surgery in May. Surgery fixed it and I should have been ready to ski in November, way too cold to not "let it heal longer". I did actually use the Power Vest with the torn triceps, even the day before the surgery. I was skiing on Jumpers, just trying to feel like I was skiing. With the straps shortened up putting zero pull on my elbow I even managed to run a few 24mph passes on my jumpers without the benefit of triceps. My current plan is to get back in shape by taking 20 to 25 sets on my jumpers figuring out how to ski with the Power Vest, just repeating passes at 24-26. My hope is that when I then transition back to my slalom ski, the vest will be a non-issue and I can get in shape to ski with the vest, then ditch it if I feel strong. I did find that it was much easier to get used to the vest while skiing slow on jumpers.
I also agree with the comments on weight. That thing must weigh 10 pounds, and that is the last thing I need on my slalom ski when I am very weight challenged from missing an entire ski season :)
Also, here is a little eye candy for all the gearheads (and jumpers) out there, just unwrapped yesterday.