The colour red can be visually interesting where appropriate, but too much red can cause people to become upset, not to mention aggressive with a repulsive perception.
Being cautious with the amount of red, and also using other colours in digital presentations and printed publications is highly recommended.
Figure 1: A case from www.audi.cz – nearly three-colour appearance with too much red colour.
* Update: The amount of red colour has been stabilised
afterwards 
with a multicolour appearance.