Since the earliest applications of quota sampling in the early twentieth century, there has been a wealth of references to its unsuitability for some purposes, such as to obtain population-representative samples [1] -[6] . Most of the criticism focuses on its non-probability nature (which precludes the possibility of calculating sampling error), and the heavy influence of the interviewer in the choice of ultimate respondent. Nevertheless, non-probability sampling methods remain among those commonly used by the majority of private opinion poll and market research companies [7] [8] ; among others, whose predominant approach is quota sampling within households previously selected by the random methods [9] . Without denying the issues raised, the research sector has responded to the above mentioned criticism, which emanates mainly from academics and statisticians [3] [10] , by claiming that these samples “work”, and, in fact, sometimes deliver better results than those obtained via strictly random sampling methods [5] [8] . The aim of this paper is to compare sample quality and response to the survey across two probability samples based on the municipal register of inhabitants and one that uses probabilistic cluster sampling combined with random route and quota sampling within the selected clusters in order to define the ultimate survey units. All of them use the face-to-face interview as the survey procedure. The hypothesis to be tested is that it is possible to achieve the same degree of representativeness using a combination of random route sampling and quota sampling (with substitution) as it can be achieved by means of household sampling (without substitution) based on the municipal register of inhabitants. According to Bauer [9] “there are few studies focus on to assess the quality of random route samples”, and this one adds the use of selection with quota methods inside home.