ELT materials evaluation is an important professional activity for ELT professionals. However, there are questions on who should perform the evaluation. Although there is a recognized importance of collaboration between researcher and non-researcher-teachers, some scholars have raised their concerns on the possible divergence between these two groups of teachers. Hence, this exploratory study sought to examine whether researcher-teachers (i.e., actively engaged in research) and non-researcher-teachers (i.e., not actively engaged in research) diverge or converge when evaluating ELT materials. The participants in this study involved five non-researcher-teachers and five researcher-teachers who evaluated the sample materials using a two-part questionnaire. These evaluators used an in-depth method because it is more focused and allows them to evaluate materials with depth. The scores assigned during validation were analyzed using descriptive statistics and inter-rater correlations. The findings revealed that the evaluation of the two groups of teachers was consistent in almost all evaluation criteria. However, non-researcher-teachers showed higher agreement among themselves than the researcher-teachers. These findings have implications for materials evaluation and classroom practices.