Louis Walsh's Overs in 2011 - Sami Brookes, Kitty Brucknell, Jonjo Kerr and Johnny Robinson - struggled in the competition and the Irish judge didn't get a single act to the final.
However, Barlow has tipped the category for success this year, describing the standard of acts as "superb".
"The category to watch is the Overs. The Overs category hasn't been taken that seriously in the last few years but it has turned into the biggest contender this year," said Barlow.
"The standard is superb."
The age limit for Overs has increased this year, from 25 to 28.
Talking about this year's overall standard, he added: "I think it's been extraordinary this year. Everybody thinks so. I have even heard cameramen saying to each other that it's such a massive improvement on
"The standard has definitely gone up a few notches. I think the audience is going to love it."
The X Factor returns on Saturday, August 18 on ITV1.
Photo Gallery - X Factor 2012 hosts and judges:
Copyright: ITV Thames/Syco