Product review (5 stars): Excellent kit. But only add one segment at a time.
The lint eater  actually lives up to the manufacturer's claim.  I found it easy to use, with clear instructions and sturdy parts.  It was able to bend along four right turns, and scrubbed out a good amount of lint.  My method: hook a shop vac to the external vent, pull the dryer away from the wall and disconnect the dryer vent from the duct, and start brushing from the inside out. That first right turn required some patience.  I would follow another reviewer's recommendation: don't add a segment until the current one is 2/3 of the way in. I made the mistake of connecting three right off  the bat. Lucky for me Gardus makes segments strong AND flexible. They got twisted into a helix but didn't crack or snap.  Amazing, too that I needed all four  segments, but still they were able to negotiate three right turns at the very end of the duct. Worth the money, but make sure that you read the instructions from beginning to end. There are some potentially very annoying and expensive pitfalls. Think about every step twice as you go along and you will do fine.