I demo'ed Enfocus PDF Review and was very pleasantly surprised.
Once we finalize our MIS/ERP deployment, I am sure we will try to replace Insite with PDF Review.
Hopefully by that time PDF Review will be on version 2 with even more features and more mature.
-Major benefit that I see is that is vendor neutral, it does not mater which workflow you are running, you can tie PDF Review with anything and everything at the same time.
Also, you are in full control of the PDF and what you want to do before and after the review.
No need to manage clients and administer it.