I'm not a high-elo player. But my friends on higher elo thinks this build works great.
-A lot of damage.
-Positioning is easier considering you can spam your Q spell from a long range.
-Can do both midlane and botlane.
-You can spam forever considering you have a lot of mana.
-Little attack speed.
-Weak early game before you get your core.
-Your Muramana will drain a lot of your mana so check if it's on often.