I also have no problem with Ayako, and think they get a lot more flak than they deserve.
However, I did switch from them to Taka a few episodes in after trying them out for an episode. This was back when Ayako was still releasing HD too. Taka seemed to have a cleaner picture, and their translation and editing seemed to have a better flow to it.
Yuurisan worries me because they do have a habit of taking liberties with their translation, which is usually meant to make it work better in english, ended up making some things sound silly, at least that's how Jigoku Shoujo was, and that wasn't too long ago.
That seems to be the only XviD/SD release, so we may as well get that uploaded now and then sort out the HD situation between Ayako/Taka/YuS when it's available.
I always assumed that 480p usually meant SD?
It does, Taka's 480p is a clear winner in that department. The Ayako xvid is exactly what it should be, a speedsub with poor image quality. It serves it's purpose(it's what I watch the first time around), but has no place on an archiving site.
So, in my opinion it boils down to Taka and Ayako for their HD releases, but from what I've seen from Ayako's translations in their Xvid, I would rather have Taka for both definitions.