Checkout Improved/Worsened by installing quick ship cost calculator?

[houstoncory]

Im considering installing a quick ship cost calculator on each product page, that when a zip code is entered, the shipping cost for the particular page shows.

 

Have any of you already tried this ? If so, please share your experience with this, as Im wondering if it would help, or even worsen checkout rates..

 

Discuss..

[houstoncory]

Anyone use this add on ?