I use unstable in my day to day and have had minimal problems.

Same here, my laptop as been on unstable for over five years and it's been fine.

Unless you need Debian for some reason, why not use one of the arch based distributions or fedora/some other redhat based one? Those always have the latest packages.

I don't get the question. I already have the latest packages on Unstable, why would I switch?

Does testing get timely security updates? Last I checked (quite a while ago), it explicitly did not.

It gets them with regular delay of testing unless it's high priority. See:

* https://www.debian.org/doc/manuals/securing-debian-howto/ch1...

* https://www.debian.org/security/faq#testing

That's what I meant. Security support for testing seems to be documentedly behind stable and unstable.