At first I didn't like Energy Transfer. The HP loss wasn't crippling, but it could be living on the edge depending when you used it - IE bank vault missions.
Now that I have it slotted some and the hp loss has been reduced (btw, that has helped a lot.. 130 health a few levels ago now down to 96 health at level 33) I use Energy Transfer regularly.
Even if you BU before AS, you can get off ET then TF and usually a Bonesmasher before it's gone. That's easily 3 mobs killed in less than 10 secs.
ET is also nice for PvP. AS is 4 seconds w/ interrupt and TF is 3 seconds. BU -> ET ->. Placate -> AS is a decent combo. Or replace the AS depending on whether you'll be able to get it off or not.
Energy Transfer has become a main part of my attack scheme. Even though at first I hated it, lol - I even took it off my bar for a while.
