actually, I don't know how to judge this app, it works but function not good if your website has a collection on homepage or collection it will not work, this upsell only work while the customers add to the cart by product page, if they add to the cart from homepage or collection page, which will not pop up an upsell suggestion for you, I think this is what this app should do better.
I love this app, coz others app only works while customers check out or in the cart, this app works at to cart at least, but still awaiting for doing better if it works for homepage and collection page add to cart. that's my suggestion
Hey! Actually, our app works on any page(including collection page, home page, etc), but sometimes we need to take a look to adjust it to work on your theme. Also, we have many API's to integrate 100% with your theme, our API is very complete and easy to use, is good for stores that wants 100% of integration. Please contact our support, we can make it work anywhere you want. Have a nice day!