Quick2Cart is a super flexible Social Ecommerce shopping cart with Multi Vendor, Multi Store & an awesome JomSocial Integration. Downloadable Products is a much awaited feature.
Here is a sample digital free product. You can download the free sample file. Buying this product you should be able to download the paid files of this product.
My Downloads menu, lets you find all the downloads you have purchase, which you will find via the Menu alongside