AV Goodra is pretty bad.
Sure it gets 3HKO'd by Greninja's Ice Beam instead of 2HKO'd but due to diminishing returns you're better off with Leftovers against most neutral/resisted hits.
For example Gengar's Shadow Ball is still a 5HKO against Goodra, factoring SR damage, whether it's holding Leftovers or AV. In this scenario Lefties are clearly the better option since they'll recover health on the turn Gengar switches out (unless the Gengar user is so stupid to stay into something it can't even 4HKO).
In short, in order to qualify as a good AV user, the following requirements must be met:
-not minding losing access to non-damaging moves. Pokemon that heavily rely on them, like Celebi or Blissey, should never run AV
-resistance/immunity to entry hazards
-immunity to passive damage (Poison/Toxic, Burn and Sandstorm being the most important). Abilities that take advantage of negative status effects like Guts also qualify
-access to recovery in the form of draining moves (backed up by decent offensive stats) or Regenerator
-having enough of an offensive or disrupting presence not to become setup bait. By "disrputing" I mean access to moves that discourage setting up, like Dragon Tail, Scald or Knock Off
-good physical bulk. Without that an AV user would be just a worse Chansey with no status moves
Note that it isn't necessary to meet all these requirements at once. However the more of them are met, the better AV user a pokemon is.
