A Virtual Reality (VR) environment is being developed for CNC machine tool training purposes and as an alternative to traditional workshop-based teaching. Currently, the supported training activities involve familiarizing the user with the machine tool main components and controls as well as typical tasks such as positioning the axes and manually inputting and executing G-code commands. To evaluate the effectiveness of this environment and to gather feedback for its ongoing development, a structured questionnaire approach was adopted involving a group of 18 users with limited to no previous experience with VR and/or CNC machine tools. Each person initially used the VR environment to learn how to perform the above tasks and was subsequently asked to replicate them on a similar, real CNC machine tool. Aspects assessed include ease of use of the VR system, realism and immersion, learning effectiveness, ability to transition to the real equipment and engagement. Overall, the effectiveness of the VR environment was favourably assessed and specific suggestions for further improvements and additional features were collected.