Their plugin is the best one I've seen out of all the apps similar to it so I bought it. It wasn't perfect but I quickly reached out to them and Pham was quick to respond and made sure to accommodate and make all the changes I needed on their app.
App is not perfect at first but Pham was awesome to make it perfect for us. Best customer service, I've ever received from one of the Shopify app developers.
The Herb Farm Nz
Excellent app, had some initial issues but the developer was very helpful and within a few hours had new functionality (as per my request) and all running smoothly. Highly recommend giving it a go.