I think you should craft that deck only if you really like it. It's not very reliable. In different metas it can both suck and be Tier 1 so it's not so safe to craft him if you are looking for competitive deck. I crafted him as soon as KFT came out because I really like that deck not because I wanted to hit legend or something.
When I play Exodia Mage now I'm just taking turns matching up against a Priest(usually win) followed by a Hunter(90%) lost then a Shaman(80%) lost. So it's mostly a waste of time, at least before the nerfs there were many Jade Druids along with Priests you can get wins on.