The research reported in this paper seeks to advance the discussion on cultural usability and its implementation among non-western users. This investigation focuses on the effect of culture on the quality of usability evaluation results among Kenyan young professionals and Kenyan farmers. Literature review and field observation studies were used to develop a theoretical framework, which in turn was used to scaffold a usability evaluation method 'Harambee', depicting working together during the evaluation exercise. The 'Harambee' and Retrospective Protocol methods were implemented and usability results compared. The quality of the farmers' usability results consistently improved with the 'Harambee' method but not so with the young professionals. Despite being from the same culture-group, the effect of culture on quality of usability results seems to differ among high-end and lowend users. Consequently, when adapting UEMs, there is a need to go beyond the national cultural level and focus on the user-type too.