Go for it Detmer. I know as of around summer '09 all the new trailers were getting this kit from the factory. Mine didn't come with it. Drove the factory hangers for 6 months, then made the mod. Factory Lippert bolts were already oblong and showing wear.
Trailer honestly rides a good amount smoother with this kit. Much more beef to the components vs. stock. I highly recommend doing it.
For my tandem axle, it was only $190 add'l ($175 for parts) for a local shop to install it. They were done in 2 1/2 hours and well worth it in my mind. A guy can do it in a day on his own, but I felt it was worth it to have a shop do it for that cheap. Not sure how much more $ for a triple axle...