Anyone found good use for Spellbinder?

Tried it but it feels very lackluster. 100 AP sounds nice on paper, but it takes a hundred spellcasts just to cast it once at maximum power. In laning phase, that's waaayyy too long to stack. It stacks much faster in teamfights, but by that time, the 100 bonus AP really doesn't mean much, especially with all that utility you are trading it for.
Also the four second duration makes it very hard to use efficiently. Maybe if the duration lasted 8-10 seconds instead. Maybe the bonus AP could stay longer since 10 seconds of movement speed boost is too much.
It was created to fill the void left by the old Luden's Echo, but it lacks Luden's flexibility. Old Luden was good for waveclear, poke, burst and bonus ms. The bonus damage is also up very frequently.
Maybe someone really likes that item, or found some deadly combo with it?
build it.
I feel more rewarded going
or
/
rather then binder, which doesn't do anything outside of its base stats unless I pop the active mid-fight and actually have a respectable amount of AP to effectively use that active. Figure this, rush an item that gives 100 AP and locks 100 more AP behind an active you have to stack, or rush a pen item so you do more damage to the target via ignoring their resistance.. or going an item that gives 120 AP and automatically gives 40% bonus (so if you have base 200 AP you'll get a total of 120 + (0.4 x 200) = 200 AP.