If you don't want to loose ceiling height, you will need to remove the celing covering to gain access to the floor joist cavities.
A product we've had great sucess with is Roxul (http://www.roxul.com ... read more
I think you really need to see both on a home and decide what looks better to you. Vinyl will be cheaper and is a more modular system and less prone to leakage and installation errors.