Hmmm, actually Cymbalta is the newest antidepressant on the market. Luvox has been out since the early 1990's, each physician is going to have their own opinion regarding which antidepressant works best.
If you are looking for energy and to lose weight I wouldn't suggest looking for it in an antidepressant. Practice a healthy lifestyle and drink plenty of water will get you on the right track. In the mean time you physician should be able to recommend a antidepressant that is appropriate for you.