The volume, variety and velocity of products in software-intensive systems product lines is increasing. Product comparison is difficult when each product has hundreds of features. Reasons for product comparison include (i) concern for sustainability reasons whether to build a new product or not (ii) evaluating how products differ for strategic positioning reasons (iii) gauging if a product line needs to be reorganized (iv) assessing if a product falls within legislative and regulatory boundaries. We will present a product comparison approach using similarity matching. A product configured from a product line feature model is represented as a weighted binary string. The similarity between products is compared using a binary string metric. The allocation of feature weights is contested. We will describe one weight allocation method based on a feature’s position in the feature model. We will discuss the benefits and limitations of this method using a mobile phone example. Some additional motivations of this tutorial are: (i) to provide an opportunity to reflect on how some significant societal and behavioral trends are affecting what software we build and how we build it (ii) to draw a modern attention to the role that software reuse techniques can play in the context of societal concerns about financial and environmental sustainability (iii) to encourage a wider search for software and computing research inspiration given that product comparison techniques and binary string metrics have been deployed in many other fields e.g. biology, ecology. This tutorial is aimed at product managers, product line engineers, requirements engineers, project managers, software engineering computing staff and PhD students who want to learn about software product comparison. Attendees should have some knowledge of requirements engineering and the problems of developing medium to large computer-based systems