Which Customer Success Software Is Ideal for Large Service Providers?

I want to start a discussion about customer success platforms—specifically those that can support large service providers managing complex customer operations, high ticket volumes, and large account portfolios.

These platforms are currently top-rated in G2’s Customer Success Software category:

• Gainsight Customer Success – A popular choice for enterprises, Gainsight is often praised for its deep analytics, account-based insights, and journey mapping tools. It's especially useful for large teams coordinating across departments, but how well does it support services-based models versus traditional SaaS?
• ChurnZero – Designed to track behavior and personalize the customer journey, ChurnZero works well when visibility into usage is key. It supports task automation, CRM sync, and alerting workflows, but does it scale smoothly for teams managing hundreds of clients at once?
• Totango – Totango’s modular approach is useful for large providers with diverse client segments. It supports multiple success workflows out of the box and offers strong customer journey tracking across touchpoints. Its built-in segmentation could be a strong asset for multi-service providers.
• Salesforce Service Cloud – A go-to platform for service-heavy organizations, especially those already invested in Salesforce. Known for its unified customer view, AI-driven case routing, and robust automation. But how does it perform specifically for CS teams, not just support desks?
• Freshdesk Customer Success – Built to extend Freshdesk beyond support, this solution brings in success planning, health scoring, and customer monitoring. A good fit for service orgs that already use the Freshworks suite and want to streamline both support and success in one system.

If you’ve worked with any of these platforms in a large service environment, I’d appreciate your thoughts. What features matter most when managing customer success at scale? Which tools actually help drive retention and upsell for service-based businesses?