What i don't understand is does the bonus only apply to the droid or does it stack? ie. if you have companion with +1 crif for foo and you get droid sensor +1 crit for foo. Does your crafting companion craft foo with +2 crit or do you have two companions with +1 foo crafting?
Two companions with +2 crit. With mission and gathering skills, this helps a lot. With crafting skills, it really doesn't matter -- you only really need one character crafting.