LBX are good for crits not so much because the +50% crit but because they have lots of hits, particularly the lightest ones. A 2xLBX2 have 24 hits, each one with its roll to crit (after hit the mech and after hit the exposed location). Then SNPPCs are quite good, because they have multiple hits and also are good weapons besides that (the +10 dmg variant), with good damage, decent-good range, no ammo dependency, and a small debuff. The bad side is that in principle (also matters how damage/weight efficient it is) the more hits a weapons has the worse it becomes for Precision Shots. The LBX2++ would be terrible for precision shots, but its damage/weight is such that it is okish for that, and very good for non-PS.