HAZOP ALL THE WAY 
We haven’t even seen that much of the armor yet.
Really the only set of spartan armor I’ve gotten a good look at is the Chief’s new armor, so I guess that’s my answer 
The Chief’s armor!
I need to see more armor than just snips and bits here and there. So far, my preferred helmets are the Soldier, Scout, Locus, and default.
Link to pre-order special armors and variants.
Are we positive this is ODST? It looks similar, but I’m still having my doubts.
The CIO action figure has totally changed my mind about that armor. I now really like CIO (though I’m still waiting for Security).
The freaking LOCUS HELMET! Its the only thing that reminds me of the haunted pilot helmet. I hope it returns back in halo 4,but if it doesn’t well i always have the locus helmet to remember it by.
I love Scout and the one that shares similarities with the ODST armour. They’re my favourite so far. 
Although, 343i said ‘we have seen nothing yet’ and that there’s ‘much more armour to come’, so that is set to change, hopefully.
Mark V
From what I’ve seen I like full Mark VI with recon torso.
Deadeye. Its the only Halo 4 helmet that looks good, besides Chief’s
Mark VI, Orbital, Locus, CIO
HAZOP and RECON all the bloody way
Venator
the one with cup holders
Vibrator armor, its the most powerful ever
CIO FTW!!!
Im tied between the circuit armor with oceanic skin VS the Spartan-IV armor with the limited edition skin.lol
Venator looks interesting to me. 