I use API but think about getting the $100/mo plan and using API for overflow if it occurs.
But I have slow months and think that might not actually be the winner. Basically I'm going to wait and see before I sign up for auto-pay.
Giving how expensive Claude Code is if you use API key, I think it's safe to assume the subscription model is bleeding money out.
I'm a fan of having both a subscription and a usage based plan available. The subscription is effectively a built in spending limit. If I regularly hit it and need more value, I can switch to an API key for unlimited usage.
The downside is you are potentially paying for something you don't use, but that is the same for all subscription services.