Their translations were worse as Mixx Magazine. No.
Honestly, I think most are decent except the ones that are altered for a younger audience. Del Rey are pretty fucking good. Tokyopop still need to clean it up and tighten reins. Viz can churn out good translation, but their editing sucks ass in some titles.
I can safely can Tokyopop did a better translation for Loveless than the scanlation group that was working on it. It REALLY depends on what translation team is working on what title.