The app is not horrible, But has three issues that pushed me back to using Shopify shipping.
1. this app does not import your product weight forcing you to always modify your shipping weight. Shopify, all my products and shipping material have accurate weights so there is nothing to modify.
2. Have to navigate multiple screens to get to the point of printing your shipping label. Shopify, it's all in one screen with a pop up for your printer.
3. Tested 5 packages and Shopify and Pirate Shop were 100% the same shipping rates.
In summary, because of the multiple screens, modifications and same pricing the logical choice for me was to go back to Shopify for my shipping options.