After i started botting on my laptop with the same Mech Mage deck, i got slightly better results.
Winrate is 71,5% after 250 games. I assume the winrate is higher than before because its not the start of the season anymore.
I also had to replace Enhance-o-mechano with Polymorph and 1 azure drake with an owl. Both are working well if you simple don't have the cards.
The deck becomes very cheap to build once you get rid of the enhance-o-mechano. I do have 2 Azure drakes, but i still prefer to play 1 owl just to get rid of sludge belcher and other big annoying taunts.
Overall I recommend this deck, it has a decent enough Winrate with above 70% and is very very cheap.
This test was done with Default AI, not silverfish.
http://gyazo.com/a5fa824454c783a4eab89c509ffb0cf6
+1 Owl
+1 Poly
-1 Azure Drake
-1 Enhance-o-Mechano