McNulty was named man-of-the-match in the Hatters' friendly win.
"It's good experience for players like myself to play against these type of players, but Benteke has only reported back for training a few days ago," McNulty told the Birmingham Mail.
"I think if he'd had another week's training in his locker it would have been a harder night.
"He's a world class player and playing in the Premier League, that's what kids growing up looking at him will aspire to.
"It's a whole different level when you see some balls flying past you and he just brings them down with a stretched leg and knocks it past you with pace."