Ok so I've been playing Storm Brand and Winter Orb a lot, obviously Winter Orb a lot more last few days. Both characters are very well geared, though SB has better skill gems (almost all 21/20s) while Winter Orb just has a few 21/20s (mainly Winter Orb itself).
Here's kinda my assessment between the two.
Map Clearing: Storm Brand just melts everything and with HH run speed and moving around everywhere, nothing lives, at all.. so long as its not TOO far from you (SB clears 80% of the screen at least, sometimes more). Everything just insta dies, including rares. Without HH, it would still be fine, and totally playable, just more limited to run speed. However, playing storm brand in my case, and not being very good at "navigating" a map, causes me to miss a lot of monsters, even though it more or less clears a full screen, there are many areas I have to run back to clear. For some reason I'm not totally sure of right now, Winter Orb does not have this problem. Perhaps, Winter Orb has a larger range and is able to kill off areas off screen that I miss naturally. I find myself at 0 monsters remaining much more with Winter Orb than Storm Brand. Storm Brand requires much less stopping to charge up brands, especially with a level 15 brand recall. If recall isn't up, you still need to cast a SB on a pack, but this requires a split second to do, in fact you barely even notice it (It's much less time than a WO charge). Winter Orb requires a lot more stopping to charge up, even if this stop is just 1 second time, it seems like you are very often stopping to recharge. I find this a bit annoying, however, given the ridiculous power of the skill, it's a sacrifice that they have to put in otherwise it would be insta-gib everything. At the end of the day, it will come down to whether or not you're good at navigating a map to ensure you go everywhere to clear everything. If you're really good at navigating things, I think storm brand is better, but for a more dumbed down way to play, and an extremely forgiving build, Winter Orb is the winner here. My personal preference is difficult, but I am leaning a little more toward Winter Orb than SB for next league to experience it from the start. I'm surprised that its been nerfed once already, it must have been
STUPID last league.
Bosses: The winner here isn't even close, it's Winter Orb. Winter Orb absolutely obliterates bosses in lol worthy fashion. It's pretty astounding that even without RF up and probably at 30-40% the total potential for this build, shaper can die that fast. Some other bosses, like the beach boss in an elder map, will die as I'm still running to him. Winter Orb is an exceptionally powerful single target skill.
Overall: I do think Winter Orb gets the prize here. I still love to play Storm Brand and I think its a solid skill and solid build, but the lack of single target storm brand damage and the absurd amount of Winter Orb single target damage makes the overalll experience of Winter Orb quite satisfying. Just be aware that to do it "right" and to truly obliterate everything, you'll want to invest a good solid 30-40ex into the build (not counting HH). You can get by with much much less (Winter Orb is super powerful even with just 1-2ex of gear) but we're taking balls out here.
Thanks
Deathwing
for the convincing in guild chat, and I think I'll actually be able to go for 36/40 with this build.