We had a good group of 15 people, ranging from 18 to 34 (lots of tanks and healers) and the boss on Coruscant smoked us in less than 1 minute. We used interrupts but most times they wouldn't work, which from what we ere told is NEEDED to stop his super attack.
If anyone has some good tips for taking him down, let me know as I seriously have a grudge with that big tin can!
Force armor do wonders against that, and pretty much everything in the game. Have your healers cast that on everybody, above all, the ones who get targeted by that ability. Also, whoever says "interrupts herp derp" has obviously never seen a PvE bossfight, some of the bosses have a buff that makes them immune to interrupts, and pretty much all of them has one against movement debuff and stun.