I have been using Drupal 6 with Ubercart 2 for an e-commerce website I built.
I am re-creating the site using Drupal 7 with Drupal Commerce. The payment
gateway used will still be Sage Payment Solutions. This module, in the
"7.x-1.x-dev" version is still requiring "Uc_payment" and "Uc_credit".
I emailed the developer of the module asking, "how can I enable it to work with Drupal Commerce without these requirements?" The answer I got was, "We developed the Sage payment module to only work with Ubercart."