Hi guys,
Just wondering for 2H pyromancer is explosive strike worth investing in or does brimstone pretty much make fire strike an AOE skill?
Wanting to know as getting to brimstone takes ALOT of skill points!
Cheers
I play dual pistol pyromancer (72 at the moment), and brimstone is a key mastery.
The explosions goes quickly to 8 fragments, deals ~150dmg without any kind of bonus to chaos/fire (and you will have a HUGE amount of these + insane debuff)
The radius of brimstone is way bigger than explosive strike. Moreover, the 50% of +x dmg is not really a reliable mechanic according to me.
For me the answer is simple: you cannot avoid brimstone if you play a firestrike based build 
Fragments only activate when you use a ranged weapon. That being said, Brimstone still adds good damage for a melee build unless you’re focusing on pure lightning damage (I’ve seen builds stop at Static Strike). Even then, brimstone is still pretty good.
Edit - I suppose you could be using 2H ranged weapon, so my response could be mostly useless. Sorry. 
They’re both worth investing! Actually, they’re your top-priority skills for AoE damage, and when leveling a Demolisher, i actually just rush both as fast as it possible, skipping all other skills.
Do note - extra physical and burn damage from Xplosive Strike has FULL effect in AoE (3.5). It isnt diminished by weapon damage, because it’s innate effect of the skill.
Sure, for dual-wield, those skill are much stronger, but even for 2-hander, they’re amazing! Max them as fast as you can, get bonuses to them on your gear pieces - and you’ll rock!