Hey
Viktor Iwan did a cool video showing the Free Object in action.
I think the main 'con' is that it can only store in one table compared to a Seblod form for an object which stores in at least three tables.
As Viktor shows, so long as you have the 'Free Content' referenced in #__cck_core then all should be good
For what you are doing it sounds like a good example of when you could use Free Object