The HDSPe ExpressCard uses RME's own audio bus, already known from the PCI version, operating in combination with Multiface II, Multiface, Digiface and the RPM DJ interface. This way RME offers a seamless upgrade path to the faster PCI Express computers. Current RME interface owners will not lose investments made for HDSP breakout boxes when changing from Cardbus to Expresscard interfaces. HDSPe PCI Card and ExpressCard are simply the best interfaces for professional audio - no other solution can keep up regarding low latency and lowest CPU load. Also in regards of competition RME's HDSP system is still unsurpassed. No other manufacturer offers such a flexible, robust, performing and expandable solution.