The time to judge AM's capabilities as a Villa manager will be about three months into the 2012/13 season.
By then he will have had three transfer windows to get rid of players he doesn't want and to bring in players he thinks will do a good job.
I'll grant him leeway this season because it will be his transition season, but by this time next year we should have a good idea what HIS team will look like.
All the talk about him being "The New Saunders" is well premature. Yes I can see the similarities in their personalities and their approach to discipline, but being a strict disciplinarian in the dressing room doesn't bring success by it's self, you also need the force of personality that makes the players want to play for you week in week out. From what I've been told by people who know, Mr. Saunders had both these qualities in spades.
So in answer to the question, AM could turn out to be a real gem. But I'll reserve judgment until he's just finished building his third successful Villa team, we are League Champions and in the latter stages of the Champions League, and he has walked out in a huff and joined one of our local rivals and promptly relegated them!!