Conversation so far:
Did U and  Don't Don by Super Junior have success?
Super Junior's U exceeded 400,000 downloads within five hours of release. Don't Don became the second best-selling record of 2007.
DidSuper Junior go on any tours during 2006–2007 with U and  Don't Don?
Are there any other interesting aspects about this Super Junior article besides that U exceeded 400,000 downloads within five hours of release and ultimately surpassed 1.7 million downloads, crashing the server?
In late 2006, Kyuhyun, Ryeowook, and Yesung formed the subgroup Super Junior-K.R.Y., Super Junior's first sub-unit.

Question: Was this subgroup also successful?
Self-contained rewrite: Was subgroup Super Junior-K.R.Y., Super Junior's first sub-unit also successful?