Rated 1 out of 5 stars

Idea is great, execution is terrible. When attempting to sync across FF and Chrome (the ONLY reason I installed this), it locks up both in Firefox and Chrome. It also screws up the bookmarks when uploading/downloading and puts them into the different browsers in different locations/orders, it gets confused by bookmarks in folders, and to sync more than a thousand bookmarks, they want $30! Dishonest and terrible, I could not get them to give me a refund when it did not work.
Additional: "back up your favorites" ummm Firefox DOES THIS. By itself. Without any extensions. You just have to log into a FF account.

This review is for a previous version of the add-on (15.1.8). 

Terrible, locks up Firefox, waste of money Rated 1 out of 5 stars

This extension is beyond terrible.
First, the free version is only enough for 1,000 or so bookmarks, which is pretty small for a power user. Paid version is unlimited, but its $45!
Second, it is poorly written and locks up both Chrome and Firefox. At first, it just was locking up whenever I tried to sync new bookmarks to or from either browser. I FINALLY got it to start working....and now every time I open Chrome or Firefox, both lock up on black screen for 30 seconds to a couple minutes before I can start using them! Both browsers also randomly lock up for 10-30 seconds. If I disable EverSync, all those issues go away. I have asked for a refund twice now and each responding email was questions about my problem and excuses but no refund.

This review is for a previous version of the add-on (13.1.1).