Copilot Studio vs Custom LLM Stack

For enterprise AI agents, are people sticking with Microsoft Copilot Studio or moving toward fully custom LLM orchestration stacks?

We’re debating between:

• Copilot Studio
• Semantic Kernel
• LangChain
• Azure AI Foundry
• custom RAG pipelines

Main concern is scalability + reliability for Dev Support automation.
Would love to hear real production experiences.