RFID technology promises to improve a broad range of processes in logistics and manufacturing. However, market acceptance of RFID develops slower than anticipated. One likely reason is the difficulty to evaluate the resulting effects beforehand. A lot of research has already been conducted on how to assess costs and benefits of RFID investments. But until now the focus has mainly been on logistics applications. The manufacturing domain still lacks dedicated models for the costs and benefits of an RFID rollout, especially concerning the intangible, non-quantifiable aspects of such an investment. In this paper we suggest some guidelines assessing both the quantifiable and the non-quantifiable aspects of RFID in manufacturing. We present a structured model that guides decision makers along crucial trade-offs in this particular domain. Our work is based on case studies conducted at production plants in different industries.