I got these to replace 2 set Sennheiser CX 300 II that had ear bud die, To me the CX 300 II sound pretty similar, R6 has more bass though The cables are well ALOT louder then the CX 300 II and by this I mean anything touching or moving the cables results in pretty loud and distracting noise in comparison to the CX-300 II these are not for use with sport activity or anything that you moving constantly with. cant comment on quality and durability as I just got them. Gona see if wire noise less before I make final judgement or keep them.
Pros: Clean sound and good Bass
Cons: Noise from wires when the move is annyoing