I've shot the Tavor and own a AUG and FS2000. I don't have any plans to get a Tavor.
Some general observations about the three bullpups:
CHs-
The CH on all three is in the right location, but I'm concerned that if the Tavor rifle is dropped on the left side you might break it. The FS2000 and AUG solve this by using folding CHs, which does add complexity. The Tavor is also lacking a FA function, which the AUG and FS have.
Mag release location-
The Tavor has the mag release placed for fast activation but I'm concerned that it could be snagged or otherwise activated. The AUG's mag release is decently shielded but requires some manipulation to reach. The FS2000's mag release is darn near perfect, forward of the mag, well shielded, and easy to actuate by either hand.
Feel-
The AUG is slim, heavy and well balanced, kinda like dating a gymnast. The FS2000 is bulky but not dense. Almost like water wings. The Tavor is somewhere in the middle, not a solid feeling as the AUG but more svelte than the FS2000.
Operating systems-
FS2000 and AUG both use short stroke pistons, Tavor is long stroke. I'm fine with either. I do like that the FS2000 and AUG both have field adjustable gas regulators, so you can blow more gas into the action if the rifle is fouled or with weak ammo. The Tavor doesn't. From a design standpoint all three are very well thought out small arms. Field stripping is easy, with the Tavor having fewer small parts to lose.
Ambidextrous use:
The FS2000 is the only rifle that has ambi ejection, a centrally placed safety and mag release. It shares with the AUG the issue of not being able to swap CH locations. Both the AUG and Tavor are lefty friendly in that they can be swapped to right side ejection, but for shooting off your weak shoulder you're going to have some issues.
TLDR version:
There are advantages and disadvantages to all three, just like very other machine designed by men .
BSW