This was one of the few modules out there that has multiple marketplaces all in one, as an etsy seller, I needed to keep track of my inventory across all channels. Many modules currently either do Etsy+Ebay or Etsy+Amazon, and it is hard to find all 3 + Walmart.
This module is fairly straight forward and is great for managing my inventory and pricing across all marketplaces to keep everything consistent. Never had any issues and the ease of use makes it worth it for multi channel sellers.
It imports orders from all marketplaces so you can ship/etc from the main admin.