Small/large refers to the amount of bass they can output, not to their physical size. :)
The real choice is up to you. I'd let it run and listen for yourself.
Set to small, the bass will be routed to the sub. Set to large, they will run full range and the sub will only take on the LFE channel.
Different room correction systems have different levels of decision making. It may be that setting all to small and letting the sub handle all bass is just how it prefers to run.
Your own ears will matter more. After calibrating have a listen, and set the speaker size, bass level and surrounds to personal taste.
The real choice is up to you. I'd let it run and listen for yourself.
Set to small, the bass will be routed to the sub. Set to large, they will run full range and the sub will only take on the LFE channel.
Different room correction systems have different levels of decision making. It may be that setting all to small and letting the sub handle all bass is just how it prefers to run.
Your own ears will matter more. After calibrating have a listen, and set the speaker size, bass level and surrounds to personal taste.