I've used all three generations of the Unicender. The current version which is on the website is a dream to use!
The wear faces are nice and smooth so the rope runs nicely.
I could post a link to the website where I have a review and pictures posted but the Darin would banish me. If you aren't sure which website to check just email me directly and I'll point you in the right direction.
According to the Arboristsite rules and regs it is "legal" to post links to other "green industry" web sites if it is a direct link (not to the home page) to a related/relevant subject.
-moss