Then yeah, definitely use it to reflect projectiles if you can act out of it immediately after reflecting.
Against Snake I would particularly use reflector on the remote missile edgeguards, once it gets reflected he loses all control over it. Watch his habits carefully first though, because he can also turn it to slow its momentum down and bait reflector. You can also smack the missile with an aerial to clank with its hitbox and disrupt its path, but do watch out because Snake will still maintain control over it.
The missile itself has a crapton of HP too, not even a Bowser F-smash takes it down, so don't try taking it down and instead get close to Snake to force him to give up control of it.