Data migration from OsCommerce to Magento CE 1.7 - repost 2

I need to convert an old OsCommerce based webshop to Magento CE 1.7 (Categories, Products). Copy of database / images will be provided and a Magento base installation if needed. The project is for magento experts only. I've already been burned by 2 developers, so please only bid if you have solid knowledge of the process involved in a product migration. The old oscommerce webshop has configurable products and 2 languages. PM me for a link to the current live webshop. I need this ASAP. I'm a developer my self, so please ask if you have any technical questions to the project.