This study focuses on the effectiveness of two commercial stimuli: displays and advertising flyers. While displays work within the point of sale and trigger a more immediate and impulsive purchase decision, advertising flyers work out of the point of sale and, therefore, favor a more reasoned purchase decision. It is used the cue utilization theory that distinguish two dimensions for perceived quality, extrinsic quality (linked to the brand) and intrinsic quality (related with internal product characteristics), in order to analyze the role of quality perception in determining the effectiveness of both commercial incentives for selling products that induce high purchase involvement and perceived risk. The empirical analysis focuses on computer products sold by one of Europe’s largest computer retailers and, combines scanner, observational and survey data. The results show that both dimensions of quality perceptions moderate the influence of displays and advertising flyers on sales, but their impact differ on each commercial stimuli. Extrinsic quality perception increases to a greater extent the effect of displays which is linked to unplanned purchases. However, intrinsic quality perceptions improves to a greater extent the effect of advertising flyers, which encourage are related more closely to planned purchases.