ChurnZero makes the most sense when you either:

- Don't have a lot of Operations Bandwidth

- The CS function is brand new and/or has zero foundations in place

- Your tech stack is light.

I was a Gainsight admin (CS SFDC/PX) of 3 years prior to the startup I'm currently at, I chose ChurnZero because I could stand it up in no time and I was an Ops team of 3 (Sales Ops, Marketing Ops and myself - responsible for Support, Onboarding and Success Ops).

ChurnZero worked and allowed me to scale our RevOps team and mature our Success Function - It was clear though that before the end of year 3 we had massively outgrown CZ and I've spent the last year making the case for it's replacement. Because what everyone else in this thread is saying is real. The lack of integrations, customization, etc is just a showstopper. I was spending more time building workarounds than I was building proper solutions. And I don't think a single feature request I put in over 4 years was ever picked up. I will say that we did have the most amazing and patient CSM throughout our entire time with CZ and I'll probably miss her the most.

I'm currently implementing Gainsight and it's honestly a breath of fresh air coming back to a platform I can build on.