TOPIC: Foam PAC construction/Lonestar boats

Does anyone have any experience with this foam PAC construction I.e. Padded keel stuff? Is it legit or just lots of extra weight in the hull?

update on the foam PAC, rots any wood it is in contact with absorbs plenty of water dug out about 250 lbs. my hull is paper thin with no core or stringers now lots of flex should i add a balsa wood core then knees and stringers or cut 1" tube in half and make fiberglass stringers can i use just 1/8 ply with epoxy on both sides or does it have to be balsa wood any suggestions or experience could help thanks