Evernote: 5; Web Clipper: 2 Rated 2 out of 5 stars
I've been using Evernote and this web clipper for almost 2 years. Evernote is great, but their Web Clipper seems to be broken too often for different reasons. Each time it stops working, I keep trying it, thinking I'm doing something wrong. Then I remember to look at the reviews, since the developers never note any problems. I see a string of recent reviews pointing out the problem and workaround, if any (the latest is to disable DTA). I implement the workaround and Evernote Web Clipper works again until the next FF upgrade and conflict.
I have more than a dozen extensions and none suffer as much as Web Clipper from conflicts and screwups.