Would combining bands with free weights create the effect you are looking for regarding the rep rate and preventing the "free float"?
Example:
DB Bench Press w/ Bands
http://www.xlathlete.com/view_exerci...xercise_id=332
If applicable, the variable resistance is also very beneficial, but one must account for the added resistance of the bands.
We purchase bands from this site:
www.ironwoodyfitness.com
Its the best price I could find for this type of band.
Milon