To optimize the performance of an active magnetic regenerative system (AMR), it is important to understand the heat transfer phenomena taking place in the regenerator and the impact of the intrinsic properties of the magnetocaloric material. With this aim in mind, four regenerators involving three different materials (Pr0.65Sr0.35MnO3, La(FeCo)13-xSix, and gadolinium) have been prepared and tested using a permanent magnet based device. This set-up allows studying the performance of different types of regenerators over a wide range of fluidic and magnetic operating conditions. However, since no thermal exchanger is used, this device provides only non-load temperature spans. First, this work deals with an analysis of the performance of the regenerators as a function of their utilization ratio (i.e. working conditions such as the mass flow rate and frequency). Then, an attempt is made to correlate the performance of each regenerator with the physical properties of these different materials.