We have Cars 2: the Video Game in our Avalanche video game collection. It is a very enjoyable game that my boys and I LOVE playing.
One thing that I feel the Cars 2 Video Game has over the Cars 2 Playset is:
Cars 2: the Video Game (35 playable characters to be unlocked in the game) + (21 downloadable characters) = 56 Playable Cars Characters > Disney Infinity 4 Playable Cars Characters
I paid $19.99 for Cars 2: the Video Game. Do I want to pay 56 x $12.99 = $727.44+tax for the complete Cars collection experience in Disney Infinity? No...I mean yes, I would eventually cave in and do that for my kids, but I wish we would have at least had the opportunity to buy and play with a Finn McMissile figure.
Info obtained from
Cars 2 Video Game Characters wiki