Aim The aim of this study was to compare the effects of two immersive simulation-based education instructional designs, immersive simulation with team deliberate practice and immersive repeated standard simulation, when delivered over the same time on the knowledge and self-efficacy of nursing students. Background Implementing immersive simulation-based education is not without its resource challenges, making it prohibitive for simulation educators to include it in their curricula. Subsequently, there is a need to identify instructional designs that meet these challenges. Design A two-stage mixed methods approach was used to compare the two instructional designs. Methods In stage one, data was collected using questionnaires and differences estimated using analysis of covariance. In stage two, data was collected from two focus groups and analysed using a qualitative content analysis approach. Data was collected as part of a doctoral study completed in 2019 and was analysed for this study between 2022 and 2023. The justification for this study was that the identification of effective designs for immersive simulation with team deliberate practice remains a key research priority following the increase in allowable simulation hours by the Nursing and Midwifery Council. Results In stage one, there was no statistical significance in the participant’s knowledge or self-efficacy between the models. In stage two, four themes were identified: vulnerability, development of knowledge, development of self-efficacy and preparation for placement. In contrast to stage one, participants reported that the repeated nature of both designs reinforced their knowledge base increased their self-efficacy, reduced their anxiety levels, and helped them to prepare for placement. Conclusion The results inferred that both designs had a positive impact on the participants. Overall, participants reported that it helped them prepare for placements. Based on the findings, wherever possible, repeated immersive simulation-based education designs should be used and not a standalone immersive simulation-based education scenarios. If resources allow, this could be either a repeat of a scenario, or if there are resource constraints to use, over the same time, immersive simulation with team deliberate practice or a similar model. Thus, giving a potential return on investment, one that supports simulation educators making those sensitive decisions regarding the inclusion of immersive simulation with team deliberate practice in their curriculum. Further research is needed into this area to ascertain the design features that maximise this impact and support a move away from standalone scenarios to an approach that utilises repetitive immersive simulation with team deliberate practice.