which kind of biopsy to do?

Hi.  I am scheduled to have an open surgical biopsy (excisional) on my left breast in two days.  I was told by my surgeon that because of the small size of my calcification clusters and the small size of my breast I am not eligible for the core needle biopsy.  I hear the surgical biopsy is a much more severe procedure, with greater scarring and a chance of changing the shape of the breast, is this true?  Anyone out there ever get the recommendation for a surgical biopsy and get a core needle one instead?   What was the outcome?