I see Arch as a kindler, gentler gentoo. So maybe not bleeding edge, but definitely an edge. You should only be there if you know why you want to be there.
That's why I said "sort of". Arch (as far as I know) doesn't provide a global way to do what USE flags do in gentoo, but the same end can be acomplished by tweaking the packages . There are also ways to apply those changes automatically, but they are not the same thing either.[1]
No, arch doesn't have anything remotely as use flags. But is 'gentoo-like' in that they serve upstream vanilla, without modifcations. I still prefer Gentoo's use flags and tolerating the suckage that sometimes ocurrs when an emerge fails.
Someone should make a way to sharing ebuilds with the same useflags and CFLAGS(or at least compatible CFLAGS) so users could opt-in and 'crowdsource' the binary generation, as I feel gentoo with binary packages would be the best distro ever (I am aware portage supports binary files, it is just prohibitevly expensive to support all configurations.
It's been years since I tried gentoo (and eventually decided it wasn't for me), so I had to look up USE flags. Great idea.
I've never run Arch, my impressions are from what I've read. Coincidentally it was the python3 thing that helped me decide not to use Arch.
Since I don't run arch (or gentoo) I don't speak with any authority. Searching around, I saw something about yaourt, which may or may not serve the same intention for the type of distro that arch is.