yes it is for marketing that they say dont change out chokes and never fire a slug through a turkey choke. and these guys sayin use mod and full. dont do that either. any time you use one of those chokes you risk splitting your barrel. the best choke to use with foster type slugs is cylinder. hence the reason that all smooth bore slug barrels are cylinder. meaning there is no constriction. as you do not need constriction on a slug. the next best is the improved cylinder. anything beyond I.C will distort the slug and while you may and plenty of people have killed deer and been able to get decent groups with mod and full it is a poor choice to use them.i have seen 3 barrels split from such acts. one was a mod barrel the other 2 were full choked.... do not use them for slugs.. if it was safe then the gun companies would make a full choked slug barrel or a mod but they dont.. bottom line it is up to you to choose but an encore barrel is pretty expensive to replace should something bad happen.