I use tab auto complete, and i think it's a 5% productivity gain. On a good day, maybe 10%. I haven't put much effort into optimizing the setup or learning advanced usage patterns or anything. I'm using stock copilot, provided by my employer. If I had to pay for it, I wouldn't be using it, as it doesn't justify the cost.
The 5% is an increase in straight-ahead code speed. I spend a small fraction of my time typing code. Smaller than I'd like.
And it very well might be an economically rational subscription. For me personally, I'm subscription averse based on the overhead of remembering that I have a subscription and managing it.
