After fighting with the JVC packaging on these phones for a few minutes to carefully open them in the event of a desire to return them, I was able to get them out of the package. The buds were pre-fitted with smaller ear pads and the mediums were still in the container for use, if desired. I realized that I'd need the smaller pads - which were still a slight amount bigger than I'd actually need. Having access to even a smaller small ear pad for these would be nice.
I plugged them into my Sony Walkman and listened to some Cowboy Junkies and Lucinda Williams and noticed that the sound blockage wasn't ultimate. So, I fiddled with twisting them into my ear canal a bit better - and, then, more of the outside noises were blocked out, making me more pleased. As the day went along, I was beginning to have less appreciation for the quality of bass that these buds were providing. Sure, there was plenty of it, but it was also a bit bloated and not so well defined and I started to get kind of ear and head fatigue from using these.
They're a fair headphone for the price. Surprisingly, the bass is there - for an under $20 ear bud. However, I think it's up to the listener to see if the bass is of a good enough quality for them. I know in my case, the foam pads being wedged in my ear with a bloaty bass kind of made me feel a little too closed in.
I don't think these are the right buds for me. At lunch today, I did pick up the Klipsch S4 (at 4x the price of the JVCs and am also considering the Etymotic MC5 (also at 4x the price of the Marshmallows). So far, the Klipsch is sounding pretty sweet - but, needs more break-in time. The Etymotic ... well, it all depends on if my other local Apple store carries them. The first one I went to at lunch time didn't have the MC5s. I'll add respective reviews for both of those ear buds after I've had a chance to utilize them appropriately.