I have been learning Japanese for about a year now, so I don't have that much experience reading Japanese text yet [1]. I'm aware of some of the visual differences between Chinese and Japanese fonts, but I have not yet had trouble reading Japanese text set in a Chinese font. If you have any specific examples for Kanji that are difficult to recognize in a Chinese font, I'd be interested.

[1] Although on the other hand you could argue that I'm spending more conscious effort reading Japanese text than a native speaker would.