These are just a great value! I went back to them this summer for outdoor/active use. I paired them up recently with the Headstage refurbished 3g amp. At first I couldn't get a great sound but after tinkering a bit I did. Upped the bass to the I level and increased the impedance to the III level. The bass is solid, wide soundstage, crisp highs - all for less than $20!
I do need to note that while these clip-ons sound good without amplification, they don't sound all that special. It really takes a good amp to get these to sound their best.
I had turned back to these after difficulties in getting the Blox earbuds. My original pair developed a rattle and despite haunting the Blox site and sending messages, there wasn't any indication that they would be coming back. I needed something open so that I could be aware of my surroundings. I had tried the 75's before but they also had developed a rattle after awhile. I have found out that it was using them in high wind situations that wiped them out. I take them off now when that happens and they have lasted all summer.