These things are so much fun to hunt. Sometimes you get the easy one with 20 hitpoints, and the next time you will get a smart one that chain stuns you and takes you to the last inch of your life. After you reach level 25 or so, I think the easiest way to hunt them is solo. That makes their Charm spells useless. The only time I have ever seen a group death hunting these guys was a result of a charmed tank or cleric. The biggest thing to remember when hunting them is to not panic. They will do all kinds of crazy things to you (charm, blind, dot, stun, and blast you back 30 feet), just keep wacking or blasting away and they will go down fairly easily.
The only other problem is their pet pathing. If you are hunting them in the Gorge, their pets take an odd route to get to you (if you stand by the back wall). If there is a mino or muddite in the path they will bring that with them. If I’m using my druid, I will harmony everything in sight before going after the EE.