I mostly care about the ability to test locally (both automated and manual tests), and how composable everything is (fast tests too)?
It's a simulator, works like a charm. The next version is going to be based on workerd, the actual Cloudflare runtime which they recently open-sourced.
I guess one would want support in the framework for that level of testability, but hey, one can dream.
On the client you can do whatever of course.
Vultr is cheap but flaky. It's good for experiments.