I can't speak to that particular situation, but you can get a great sound out of affordable violins, and the biggest deciding factor by far will be the skill of the player.

The biggest physical thing to stand out when learning is that you make slightly more tinny sounds on smaller violins, and you don't typically hit a full size violin until you hit puberty.

If I were to guess, his violin does sound better, but the skill would make the biggest difference in the two situations.