Not much to think about Ice Flow;it's very low dps and its extra damage for fire spells also not a big deal.In pvp you won't even use it for damaging while you have many other high damage spells.I use it only for slowing effect in PvP;just cast for 0,1 sec and slowdown target.Slowdown works good vs physical classes because they cant come closer for a while-as long as their charge is on cooldown.