has httpredir now won over the alternatives? I think I've read various opinions for and against httpredir over the years
It is mostly replaced by deb.debian.org, a CDN based solution.
There is nothing definitive yet. While httpredir is unmaintained, when it works, its reliability and performance are unmatched by deb.debian.org. Using deb.debian.org, I can get sometimes 100kb/s on a 1G connection. And it's not unusual to get a 404 from time to time.
http://httpredir.debian.org
to get optimal sources.list (automatically gives the best mirror depending on your location among other things).