Thanks bud. Funnily enough your in luck as I got to try the RE-400's at a Head fi meet so I know what you mean. Basicly the R2's are very unfatiguing but will complement better recordings. Think of the RE-400 all cleaned up without any sense of haze but just as smooth and balanced. Hope that helps. Klonatans you can find more info out on Flares Kickstarter page, basicly the difference is in the materials used for the housing, the Pro's are made out of high grade Titanium and the R2A's are made from Aluminium. Each effects the sound differently the Pro's are also the only element to feature a close packed hexagonal structure.