I've been using Feedspace since the first or second week of their launch here. It's easy to set up, dependable, and the UI is clean and intuitive. I run Feedspace across two products and it works great. The webhook support and API access make integrations painless, and the branding options help everything feel consistent.
I'm on tier 4 and very happy with the purchase. Chirag and his team listen to customer feedback and keep shipping useful updates. I've watched Feedspace improve a lot. This is the best feedback solution on AppSumo, period.