These both look very good. It'll be a hard choice between them ...
They can each improve a little bit, however. Might buy both if each of you go the extra mile - so I'll be picky with my comments here
Oldum, the text along the bottom of yours has an odd slant to it. See if you can have it curve better. Also, the shiny bit on the top left border is a bit out of place ... remove that, and make that outer rim one solid color. See if you can do something with that bit in the very center, maybe
Yak, fit the wings inside of the circle (they can touch the edge, but not surpass it) and maybe reduce the number of "feathers" on it by a little bit; maybe merging by twos. The flames are a great touch, but could be made a bit more apparent, as right now the tips don't really stand out. Also, try to reduce the overall shine.