No, 65% Ias Ith Zerker is as fast as a Shael IK maul.
65% Ith Zerker is only a 5fpa Fury?
And same for Shaeled IK. 5fpa Fury.
95% Ith Zerker will make it 4fpa.

And I'm not too sure about the initial frame rate.

For PvM, you need to take the Extra %Dmg to Demon/Undead into accounts, just looking at the listed damage isn't all that accurate. And also, IK Maul is an Ogre Maul, so it has 110 Str bonus instead of the usual 100 Str.

That Str bonus would benefit a Titan build especially.

Playing with Shield or without is a playing style, for SC I don't really want to use a shield as a druid.

EDIT:
Well, a 35% Ias Ith Zerker is crap for Druid.
11/7 fury.
65% Ith Zerker is alright...9/5 fury. (95% is 7/4)

While a IK maul, ias jeweled or shaeled will give 9/5 fury as well.

For people who are new to druid...
9/5 etc means 9/5/5/5/5 frames per attack/swing, while 9 is the initial frames, and 5 are the following-ups. (5 swings per fury.)

So no, Ith zerker is no way "5 times faster".
The best it can get is 1 fpa faster at fury.

(And that's not legitimate.)