I've worked with many professional VSTi's but the mda JX10 has the best sound! The filter sounds genuinely analog and is thick and sweet. Probably the best I've heard! Currently there is no distinct user interface, but the JX10's parameters are easily accessible without need of a manual. The sound is reminiscent of a Roland Jupiter 8 more than a JX10, which is impressive. The presets are awe-inspiring! This is the most stable VSTi and so light on the CPU! Can you believe, it's free!?!