the tavors (SAR and X95) along my mini 14 are the most fired rifles i've ever own. both the SAR and X95 are phenomenal bullpups. neither one is superior. the mechanics are nearly identical. BCG is interchangeable. don't fall for any hype that one is "better". both are great it's simply a matter of preference.
my personal preference is actually for the SAR over the X95 because i prefer the old school paddle mag release over the AR-like button up over the trigger guard. i also prefer the asthetics on the tavor. the charging handle location is a wash. it doesn't matter. bolt drops are near identical. the trigger on the X95 is lighter, although the SAR has two trigger return springs and will run perfectly fine with just one. remove that spring and you'll bring the SAR's trigger down a few lbs. just don't lose that little spring because I hear IWI won't mail out replacements
i personally don't find the upgraded trigger packs (e.g. geissele super sabra) unless shooting out beyond say 200-300 yards. if going to really stretch the rifle out then you'll want to drop $$ for such a trigger, but for defensive or 0-200 yard purposes i believe the factory trigger is a better option.
the SAR is no longer being imported, so if you want something that will sort of appreciate over time go with the SAR
regardless of which rifle you get, i have found the following minor issues with both tavor models:
1) rail height is stupid. optics need to ride higher than a typical AR mount will allow. can get extra high rings or for the X95 go with a midwest industries rail in lieu of the factory rail. expensive solution but looks fantastics. on the SAR will likely need a riser or high rings. it's an annoying issue but pretty easily fixed. just plan it out before you drop $$ into an optics mount and realize it won't work.
2) buttpad sucks. it's flat. doesn't shoulder correctliy. under recoil it allows rifle to pivot up. replace it with the manticore arms curved buttpad. best $70 to spend on the tavor
Manticore Arms - Tavor Curved Buttpad