Ducts Spray Foam vs. Wrapping
Covered in foam would be a better seal and offer insulation (minor) and sound deadening for air traveling through the duct.  It would also probably cost your first born child depending on the company, their quality, the size and access of ducts, etc.  There is duct mastic that may work better for some areas, smears around like bondo.  Maybe explain your condensation issue more in depth?  That sounds odd depending on your climate and the setup.