Don't have the OMG, but:
Aurora: Love the look and feel in the hand/mouth of this unit, as well as the extra battery life. Light on the flavor and throat hit. Tank only lasted into a third battery charge before it started leaking.
juice used was 70pg/30vg, a fruit flavor. No replacement parts offered........ not sure if the other ones out there will actually fit this unit.
vGo: This is a keeper. I love just about everything about it, except for (I know I've said it a couple of times) the extremely bright, large green ash cap. I'm afraid oncoming traffic will mistake it for a green and plow into me when I have the left arrow....

. Aside from that, I think it's a nice size and shape, the battery last a long, long time and for me, the quality of the vape is just as good as the diamonds. I think the tanks that came with it provide a great vape, too, and I've had no problems with them yet. One caveat: lack of supporting accessories, i.e. cones, chargers, etc. If you want a cone, you'll have to take a chance and order one that's the right size push-on and jerry-rig it with a homemade rubber band o-ring. So far, it's working for me well.
Edit: regarding chargers, I mean extra 420mAh ones for 808, like the one that comes in this kit. Try to find one.....