Product review (3 stars): Good except for one detail....
The product is well-made (there's really not much to it), and the directions were fairly comprehensive (for a do-it-yourselfer).  One thing the instructions don't mention, which is fairly common sense, be sure to have long shirt sleeves and thin gloves.  Otherwise while you're reaching into the dryer you'll slice your arm and hand up on the exceptionally sharp sheet metal of the dryer.  Not a big deal though.

My biggest complaint about this product: The length of the exiting arm.  It ends completely flush with the exterior wall of the dryer.  Knowing this beforehand, I would have pulled the flex pipe inside the dryer and connected it to the exiting arm first, before having the exiting arm connected to the elbow.  There's absolutely no way to connect an o-clamp ring outside of the dryer.  It made for some additional work on my part.

I'm sure someone who does this professionally would have thought to check this all out first.  But as a DIY kind of guy, I followed the instructions, then had to backtrack to compensate for the lack of external pipe for the flex connection.