I've had these for a couple of months now and can only say good things about them. Once correctly inserted into the ear, sound quality is truly excellent. I regularly listen to a wide variety of music ranging from rock to dance to alternative and the depth and range of music is (in my opinion, as they should be) far better than the Klipsch S4i headphones I tried previously. The phone control buttons are also good and despite having to get used to not hearing your voice as clearly as the call recipient (ears isolated from outside noise) people receiving calls have all confirmed that sound quality is excellent. In brief, I'm very happy with the HF3's and the icing on the cake is that they block out the noise pollution of household noises such as TV or other music I don't want to hear whilst revealing elements in music I've sometimes not noticed before.
UPDATE: I was happy as Larry with the HF3's until the cable broke. I really did look after these earphones and feel that Etymotic need to resolve this apparently (reading blogs) common issue. Thank goodness I purchased from Amazon and returned within the Warranty period.