United were relegated at the end of the 2007/08 season, but bounced straight back after victory in the League One play-off final in May.
"When you look at the size of some of the clubs the Championship, it is a lot bigger than two years ago, but that doesn't necessarily mean it is better," Hayes told the Scunthorpe Telegraph.
"I've spoken to a few people who said it wasn't as good a division last year as it had been when we were in the Championship.
"It was apparently more direct, rather than teams playing football."
Source: Team_Talk
