Have tried a few others in the past - Suredone is the first to impress me with responsiveness to questions and customizations. Additionally, their portal is much easier and intuitive than any other I have used. Posting goods takes just minutes in most cases.

one platform to integrate with ebay and amazon

I have had many problems with SureDone. It is not necessarily my favorite program to use. At times problems are resolved quickly, and other times problems go unresolved for weeks. I do like that it keeps all my work organized, and imputing information is clear and easy.