It's very easy mechanics wise, but not so easy with numbers in 10 man. You either need two good healers (~500k HPS required) or really good dps to do it with 3 healers. I find Immerseus easier, but the first three are all very easy really.
If you make sure healers soak every big add, and cleanse your dpsers fast enough you'll easily beat berserk while 3 healing. We did the same tactic week 1. Week 2 we had 1min+ left on zerk.
It's funny how it feels like the first boss on heroic of a lot of tiers felt easier than the last boss on normal.
H jin felt easier than normal Lei Shen. H Shannox felt easier than normal Ragnaros. H Halfus felt easier than normal nef. Maybe it just feels like that due to the huge gear gap in between our first last normal boss kill vs first heroic boss kill.
Yeah that is probably the reason + they want us to be able to easily kill first few HC bosses depending on size of raid.
By the way, HC shannox was easier than normal shannox :P and hc jin just imo was way harder than lei shen normal and most of the HC bosses in ToT actually, simply hate the Ionization... Imagining the fight lasting long enough without the faceroll of pools and HP pool and it would be a nightmare. (Speaking as Warrior, yeah I suck at it but still some movement increase would be nice to avoid it better...)
Not sure why people find spoils so hard. I'd put it easier than Shamans at least.
We found the DPS check to not be so easy the first couple weeks - though we ended up doing the zerg strat. I suspect that it will very quickly turn into a joke of a fight as item levels increase since there isn't really anything complicated about it at all.