I thought this was a silly, pretty dumb movie, but opinions differ, and no one singled out Justin's performance as bad. In fact, he was singled out as the major asset.
From Mick Martin and Marsha Porter's DVD & Video Guide: "Surprisingly entertaining film in the Home Alone mode that mostly succeeds due to the performance of Justin Berfield". Rating: ∗∗∗.
Another opinion from www.moviemeter.nl: "A movie we can only laugh at. Very much typecast, and I often doubled up with laughter about the dumb stock actions that took place. The only one who could act a bit was the youngest of them all: Justin Berfield". Rating: ∗