Yea, Def killer for edh, but I see other reanimator targets to be way stronger. Iona ect are simply stronger. I still like the makeshift mannaquin/emrakul/oonas prowler reanimator (but I think just hard casting it or cheating it in with through the breach are both stronger lines). Maybe some kind of gifts package in tron, but path seems to make this one irrelevant in modern.
Efficiency isn't the question, the cost matches the effect. The CMC being 8 means it being played as an honest wincon is almost out of the question. Yes its worth the 8 mana your paying for it. 8 is simply asking too much in a titan format. The worst part of this equation is we are very much in a format defined by Delver of secrets and it will either be mana leaked or vapor snagged. 8's asking for a lot and while this is worth the mana its simply not good enough (without cheating it into play). Frights playing this on turn 3 is pretty sick but its still to fragile right now.