We present an automatic technique to transform a subclass of featured transition systems into modal transition systems with additional sets of variability constraints in the specific format accepted by the variability model checker VMC. Both formal models are widely used in the field of software product line engineering and both come with a dedicated model checker. The transformation serves two purposes. First, it contributes to a better understanding of the fundamental differences between the two approaches, basically concerning the way in which variability constraints are represented (in terms of features and actions, respectively). Second, it paves the way to compare the modelling and analysis of product line behaviour in two different settings.