Alternative grading practices, such as specifications grading, have been reported to increase student engagement, decrease instructor workload, and ensure a minimum mastery of all course topics. However, there are also reports of decreased student learning and there have been few comparisons between different policies. In this experience report, we explore the effects of adopting different types of specifications grading systems in a project-based Embedded Systems course taught at a South American institution. We tested three different grading policies for exams in three different course offerings, varying both the number of times mastery needed to be demonstrated and whether exams specified two (pass/fail) or five (I, D, C, B, A) proficiency levels. For each policy, we list potential problems we were trying to address and evaluate how the change impacted the course. We use a mixed-methods approach to do a retrospective analysis, focusing on three aspects: (1) exam attendance and pass rates, (2)grades on labs and projects, and (iii) student perceptions. We find that attendance remains high and pass rates increase with the pass/fail model. Also, lab and project grades decrease after students receive a passing grade in the first exam, indicating a possible decrease in engagement with the course. In terms of student perception, students described a mix of procrastination, low engagement with the course, and a desire to learn and create a challenging project.