H spine dps

Does UH with reg gurth or H ESS have enough burst for heroic 10m spine?

We just started work on spine this week so I respecced back to DW frost with H HoM and reg souldrinker and reforged off all my exp since the tendons can't dodge or parry.

This is all fine and dandy except when it comes next week when it's time to reclear the other 6 HMs and I would go UH for Zon. With going back to a DW frost spec for spine i'm sure my dps and survival will go down a lot.

So go back to UH or stick with frost?

Just looking for opinions.
I'd think that if your goal is controlled burst that H ESS would probably better fit that role for Unholy since not only can you not control when the Tentacles spawn but also it's not easy to control what they'll attack. So for example while you are on the Tendon they maybe fight a blood or a corruption. DW Frost is considered more bursty so it maybe favored on Spine either way. But back to the weapons? I'd still think H ESS is stronger than Gurth for that exact fight.
Your survival isn't going to go down appreciably. Frost AMS will get you through anything in spine no problem. I suppose raid survivability might go down some without AMZ but if that's substantially helping your group there are larger problems at play.

Your dps should be going up as DW. You can create burst with unholy, but if played well it shouldn't be near as good or reliable as frost burst.

In the end it comes down to your raid group's dps. Are you able to consistently get the tendons down (not just the first one, at least the second) with time to spare? Then it won't hurt to go unholy, might even help by adding AMZ. But if it's close, if your getting it down with seconds to spare, stay frost.