Mains said, however, the opposition had slipped well off the pace and it might need a total rethink by World Rugby for nations to catch up with the All Blacks.
Mains, who coached the All Blacks from 1992 to 1995, as well as coaching Otago for almost a decade, said the side was well ahead of all other teams and he could not see the Lions winning a test next year.
''They [All Blacks] are very well coached, very well managed and nothing seems to faze them. I'm just astounded by the skills and vision this All Black team has got,'' he said.
''It's never boring because of the quality of rugby they are playing and the quality of ball they are delivering. But in saying that I would like to see them challenged.''
Mains lauded the forward pack - locks Sam Whitelock and Brodie Retallick were outstanding, openside flankers Matt Todd, Sam Cane and Ardie Savea were all as good as each other while hooker Dane Coles was getting near Sean Fitzpatrick in ability.
Mains said South Africa was doomed if it continued along its path of a racial equality system while Australia was being let down by some poor coaching of sides in Super rugby.
''The All Blacks are lucky because New Zealanders have embraced Super rugby. Through the good coaching there the players have improved. The Super coaches get three-quarters of these players up to the standard of international rugby.
''So the All Black coaches come along and take the elite out of the Super teams and work with them.''
Mains said he had a lot of time for Super rugby coaches such as Dave Rennie and Jamie Joseph.
He was disappointed the duo had, or were about to, take up offers offshore.
''The NZRU [New Zealand Rugby Union] should have spent money to keep them [Joseph and Rennie] here. I know there was the challenge of going into international rugby but if they had been able to stay then someone like Rennie, he would have made 30 players here a hell of a lot better.''
Mains said if New Zealand could pick a second squad behind the first-choice All Blacks and provided it has enough time to train it could be more than competitive.
The South Africans were doomed because of the stance of racial quotas which Mains said was putting the sport on the downward slope in South Africa.
Mains said the quota system had been in force in South African rugby for 20 years so players had every chance to come through and play for South Africa.
Australia was at a low ebb.
''They have three or four good players but the rest of them make a weak side. They try hard but they are just not good enough.
''Both sides have huge deficiencies. They are unable to turn opportunities into points, and neither have attacking strategies that would put a good international side under pressure.
''The All Blacks are simply playing the way they want to play.''
The deficiencies came from weak competitions in many countries.
He said Lions coach Warren Gatland would be working hard to get his side up to speed.
''Warren is a clever guy who will be looking at a certain style of player and select them to play a certain style of rugby. I think it will be a very good series but historically they have struggled here.''
Mains said whether the players were able to adapt to the style Gatland wanted to play was the question as they were playing in mediocre competitions.
He is picking a series sweep to the All Blacks although a couple of the tests may be close.
He thought World Rugby needed to have a look at the issue of weak international sides and try to improve the standard of many competitions in various countries.
It was puzzling how the Johannesburg-based Lions played so well in Super rugby yet South Africa was not copying their style.