This questions get asked all the time
No right answer as every gun is different even if its the same make and model.
What shoots out of your buddies or Joe Shmoes isn't necessarily going to shoot out of yours.
Only way to know is try different brands and test them. Costly endeavor with shotgun slugs as they are expensive.
Another common mistake people make is shooting for groups to fast,that barrel heats up and accuracy goes to crap,plastic sabots and a hot barrel don't equal accuracy
All this said, Lightfields usually give acceptable accuracy
I've spent hundreds of dollars testing slugs, learning trajectories and doping wind
12ga Browning A Bolt Federal barnes Expanders(discontinued but I have a good stash) 5 shot 3" group @ 200 yard