At present I am fire as it still a good fit but may change to FOTM arcane sometime in the interim I running with invocation but I have seen some post saying ROP is better even for fire.
Sorry for noob question but if anyone out there can advice would be appreciated
From my experience Invocation is better for Fire because it is mobile. While it does have a long cast time its better than standing in the Ring. I could be wrong, but most Fire mages play with Invocation.
Movement is a pain with RoP, while with invocation with just a little planning and watching timers it should be no problem to maintain 80%(85%)+uptime.
Totally depends on encounter, some fights can punish you for evocating and some have frequent non-DPS phases so you can't time invocation buff anyway (Lei-shi says hello). Though basically invocation is better for fire.
Invocation for most fights. The only fight so far that I haven't taken it is Garalon where I took IW as its sustained AoE damage which is almost garanteed to break the shield. Plus I was kiting so standing still for 5 seconds wasnt an option most of the time.
I mainly use Invo and use the others situationally:
ROP - Sha of Fear, not enough damage for good uptime on IW, Practically impossible to get 5.1 seconds when needed to Invo on the platforms with the add without it being interrupted by shoot
IW - SG heroic with Jade up
Then on Ambershaper and Garalon I've used both IW and Invo, both work well on these fights so it's just a preference.
Invocation works perfect for Sha of Fear, just need to time it well(2-3 pulls). For me it's like that - pre-cast, cast @ the last second of Bloodlust wait for the teleport, cast right after you're there so add isn't fearing yet, cast again behind pillar while he's using death lotus = both fearless+invocation UP. Just don't use more than 2 Evo per phase.
Tried RoP there... it felt awful when multiple adds are firing.