All this Tavor talk made me pull the twins out of the safe for a handling session... I have several bullpup style carbines, and although the Tavor trigger isn't as nice as the FN's or even close to that of the RFB, the platform is excellent... so much so that I have a pair of them. Build quality, ergonomics, simplicity etc. make for a wonderful package. I've tried the rifle with the "spring" removed, and found the trigger to mushy... I quickly put it back in and prefer the heavier more deliberate feel. It is not a match trigger, but with a consistent "press" it's very easy to fire accurately.
With respect to sight options, I've tried a few before going back to the Dlask Rail / EoTech combo for both carbines.
Good luck with your selection...