MBSE or no MBSE: is MBSE the final answer to system engineering?

In this paper we will make a revision of the usage of MBSE for an astronomy-oriented instrument. We will in particular trade the benefit Versus the overhead with respect of the traditional System engineering method. We will compare different ground-based instruments for different telescope size in different project phases. We will try then to underline where MBSE have been useful and where the criticalities of this method emerged in order to draw a possible roadmap to exploit the maximum benefit achievable by this method. In detail we will focus on four main aspects. In the first part We will compare different requirement management approaches. Second, we will focus on the Interface management which is one of the most critical elements of the system engineering discipline. We will then compare the product traditional product modelling (excel based) with respect to a database oriented one. Finally, we will assess the use cases management. We will compare traditional Versus MBSE in order to allow the reader to identify which of the two approaches better fits with its needs.