Hi Adamaley, the Tak 247b give more airy top but the KR 5U4G has more grip and fuller sound. It's systems dependent. One day, I really would like to try Tak 300b. Mine is Balance version without VC..so need to sell my kidney to obtain quad matched Tak 300b. 
@ferrox anymore feedback using the Tak 274b rectifier? Is your DAC single ended? What is your favorite tube to pair with the Tak rectifier that is not a 300b?