I'm re-watching Tenchi GXP now. I got the Funimation Viridian collection back when Revelation announced it but didn't release it. It's a show of its time, probably the best Nabeshin show out there. It certainly bears up better under rewatching than Excel Saga or Puni Puni Poemy. It's at its best when it crosses over with the Tenchi OVAs (It was bit of a prequel for OVA 3), but it's not a show that I'd have considered pouncing on the licence.
EDIT: Unless Eva 1.11 gets a reauthor, either by Funimation or AL, the only difference will be in the accoutrements and the packaging. It'll be the same disc.