I found the idea to be very interesting. My other car is an '89 Mustang GT convertible, which is FAR from a sturdy chassis. I've added some chassis stiffening braces (made a noticeable difference), and will soon install a 6 point rollbar (should make a huge difference I think). I'd be interested in finding out more about this procedure for the Mustang. I'm sure my Legacy could benefit as well, but not as much as the flexi-flyer convertible would.
I didn't pick up the magazine, just browsed through it on the newsstand - did they say how much the stuff cost? I saw that they used 5 kits (as I recall) for the 300Z, so if the stuff is expensive that would add up pretty fast.
'99 Legacy 2.5GT 5 speed sedan, '89 blown and intercooled Mustang GT convertible