I use both GH Copilot as well as CC extensively and it does seem more economical, though I wonder how long this will last as I imagine Github has also been subsidizing LLM usage extensively.
FWIW it feels like GH Copilot is a cheaper version of OpenRouter but with trade-offs like being locked into VSCode and the Microsoft ecosystem overall. I already use VSCode though and otherwise I don't see much downside to using GH Copilot outside of that.