In certain situations the mage is worse but can be better if yused right. If you play the mage with the mirror on the first draw its double lowers the cost to 0. Free draw is awesome lol. Then you have the candle take a further energy off it is great in smaller decks. Use candle with mirror also is a great way to double value.
Yeah, I noticed the Mirror + Mage synergy, but I don't really like it? Sure, free draws are fantastic but at the same time you're effectively taking a turn off to set that up, and I've found that most of the time you don't have any "spare" turns unless you've been grinding a bunch, and at that point I'd prefer to prestige.