Works well, including on 3.5.x Rated 4 out of 5 stars
Works well for me, I have several policies setup for, e.g.:
1) Personal and intranet sites that I want to run with high trust and feature level
2) Well behaved sites that need some features I normally disable (e.g. allow Google Maps to grab the right click)
3) Normal sites that get a moderately paranoid configuration
4) Sites I treat as "necessary evil", I use them occaisonally when I have to, but I assume they may do obnoxious things to my browser.
I've used Nightly Tester Tools to forcibly enable this add-on on every version of 3.5.x, up to and including the current 3.5.4, and it works fine. Would be nice if the author (or someone) would put up a version with updated compatibility markings.