Laurentiu,
JFBConnect creates 100% standard Joomla users. With either of those extensions, you'd be able to offer Facebook registration, which is faster and more convenient for users. We don't have profile plugins built for those extensions, so you wouldn't be able to automatically import Facebook profile information into them. Things like name and email address would properly be saved by Joomla though.
Beyond that, all other features (Like buttons, comment boxes, etc) can easily be added to any extension and won't be a problem.
Hope that explains, but if you have any other questions, just let us know. As always, we have a 30-day money back guarantee if you aren't able to get things working how you want.
Thanks,
Alex
jStore Pro
