One of most interesting aspects in haptic research deals with the extension of application workspace, thus allowing haptic simulation within large virtual environments. Several devices have been realized that allow this kind of interaction, in particular our interest focuses on mobile haptic interfaces, realized by combining classic grounded haptic devices with mobile platforms. While grounded haptic interfaces feature spatial limitations due to manipulator dimensions, mobile haptic interfaces are characterized by dynamical limitations due to performance of employed devices. In this paper we introduce an experimental analysis to evaluate performance of mobile haptic interface from a transparency standpoint. Moreover, some basic guidelines are presented to enhance MHI performance by setting the controller depending on technical parameters characterizing used devices.