derevka wrote:Vial is 4341 spirit for 20 sec on a 120 sec CD. So thats worth 724 spirit or 408 mp5 and its an 'on use' so you have to remember to use it on CD.
You could just macro it to PW:S to use before cast so you take the guess work out of it. There isn't really a reason to time the trinket especially mid-end fight, unless for some reason you are full on mana. Only situation I can think of where you really wouldn't want to do that might be Gara'jal when you come back to full mana after coming up.