The most expensive module for the 3 rackspace eurorack system will be Ken Macbeths X-Factor dual Oscillator so far. It will be coming in to ship from here finally next week !!! With two high quality VCOs and the wonderful ringmod based on an  AD633 that sounds like a VCS3 – indeed – is needs half of a 19″ rack 3 rackspace frame for just this. The haptical space is brilliant and the quality of the controls helps you to decide for it after you could once put your hands on it. Still it is a lot of money but after you also bought the other half of the truth, selling your old minimoog, you will know about it? Check it out yourself, we will keep one for this.