I use Reverb because it makes my rotation a lot smoother.
Without it, sometimes I'll be sitting there waiting on all my cooldowns, which then all come up at the same time. At least with Reverb, I can interrupt more often in addition to having fewer dead zones.
That said, I'd totally get 3/3 Ele Precision + 2/2 Reverb + 2/2 Call of Flames if it was possible as Enh. :3