Ferdinand said: "Edwin is the best keeper I've played with. It's as simple as that.
"The record, the stuff we've won together, the assuredness that he transmits from himself to the back four, is great.
"I also don't think I've seen a better keeper with his feet to be honest either. He's got an extra year in terms of his contract and I am sure he's got the capabilities to go and do it again."
Giggs said: "Edwin just gives that calming influence right throughout the team, with his calmness on the ball when we play back passes to him, and his general goalkeeping is sound really.
"That calming influence goes right through the team. He is getting better with age. Obviously he has got great players in front of him but, when he is called upon, he never makes a mistake.
"With the clean sheets, Edwin has done brilliant over the last two or three months."
Giggs believes it is unfair to try to compare van der Sar and Peter Schmeichel who dominated between the posts for United during the 1990s.
He said: "Is he as good as Schmeichel? They are both great keepers. You can't really compare them. They are both brilliant, both international keepers, both who have had great careers."
"In a way to achieve the record is an even better achievement because we have not been able to have a settled back four recently.
"Credit to the people who have come into the side like Fabio and Rafael and Johnny Evans. It's been a big squad effort."