i was testing jade spirit at DMF today on my 70 druid. it would proc most of the time on the first or second attack for 12 sec, and within a few sec proc again, but then no procs for along time which must have been the 50sec icd
i have not tried power torrent, i see it has a 45 sec icd, but i don't not know if it gets double "back to back "procs like i have seen from jade spirit. you might try asking in the 20-24 bracket where many twinks use it.
at the start of MOP power torrent was cheap and easy to get alternative to jade spirit, but now i see jade spirit selling 1100+g on avg and power torrent 2000+++