UPDATE: We have been using judge.me from the start. We continue to be blown away by the evolution of features and the stellar support. The broad feature set and extensive customization put this app way ahead of apps costing way more. The latest new feature: a "featured review" carousel. We've added to our home page. Great for visitors and great for SEO. World-class app, world-glass support.
UPDATE: This app just keeps getting better. We've already seen a boost in organic traffic that we attribute to our "stars" showing up in Google results on searches for our products. Today we began using the "All Reviews" page which is awesome (no pun intended)!
You can spend A LOT more per month for a product review system, but why would you when there's Judge.me developed specifically for Shopify? The Awesome Plan gives you tremendous control over just about everything: timing of requests, content of requests, and appearance of the widget. The ability to base auto-requests on fulfillment is .. awesome. So is the ability to list addresses to skip. You can also manually request reviews. Much more expensive apps from others lack these features.
This app just keeps getting better and better. And, as many others have commented, support is phenomenal. My only problem is that I can't come up with a word stronger than phenomenal.
We're presently importing our previously-manually managed testimonials into the app and plan to deploy it on our store in the next week. I give this app SIX stars.