Divine Envoys - To Use or Not to Use?

During my playing I got in a conversation with a good friend over the usefulness, or the lack there of, of the Divine Envoy. Below is several quotes from our conversation which might help to clear up a few things and express our mutual thoughts on this newest unit.

SaintScott: when I started playing again I saw the envoys and divided their attack and defense per farm space and I was asking myself, who the heck would waste favor to build these? Now look at me. lol
Although I do have one built in my attack cities for when I am offline. When you send them to a small city with no god as support, they bounce. There's one for your guide.

While this unit doesn't cost any resources,  it costs 15 favor. Its defense value, though balanced, is pathetic. Its attacking value sucks. But..... they do have a BIG bonus. At the very beginning of every world, if you do the tutorial, you receive TONS of Hera favor for completing different "missions". While this doesn't seem like much, it can make all the difference. To take more farming villages, it takes more and more population to take the next one. Simple solution. Divine Envoy. Use all your "gift" favor from the tutorials to build yourself a nice division of Divine Envoys. They are cheap, quick to build, and fast moving. Perfect for getting more farming villages quickly at the beginning of the game. If you get behind at this point, it could put you days, if not a week behind everyone else and that can mean the world to you in a very competitive world.

SaintScott: Here's a tip: If you just used 500 favor to build 33 envoys for farming village pop. That is NOT the time to switch gods. You lose all envoys in the queue AND 500 favor.