1. Will this binder open completely flat on a table (unlike the PADI binder)?
2. Size compared to standard PADI binder?
NICK W Yes and everyone in my family has one. Works great and has held up over time. Well built item and has several places to hold cert cards, Dan card or any other cards you might want to keep with your log book.
HENRY V Sorry I would not know never had a PADI binder.
BRONWYN L 1) yes it does lie flat when open! (at least mine does)
2) it is overall a bit bigger than a standard PADI binder, but not by too much... definitely thicker.
as a comment, the octopus design is a bit more muted in color in person, but I really like it a lot. Very artistic.