Where did your dc go? Were you satisfied with their options? Did they need a settling down period in their new school/college or did they hit the ground running?
Most of the schools I am looking at do not have 6th forms. At 16, some of the children get a place in a different school that does have a 6th form and some go to the feeder 6th form college. Places at schools are hotly contested. I think I would prefer my dd to go to a school rather than a college for 6th form, but a place is far from guaranteed.