I am in the market for a new set of IEMs. I’m 57, I’m probably missing hearing at the higher frequencies, and oddly, higher frequencies tend to irritate me now. I’ll often turn down the treble some and turn up the bass. My current pair crapped out the other day. They were DUNU 1000. I was happy with them, but when I bought them, I wasn’t as happy with them as I was with the headphones before them, which I can’t recall what they were. A primary concern is sound isolation and comfort. I get the Comply T-100s foam tips. I play them using my iPhone 6 right now, I’ll probably stay in the iPhone ecosystem in the future, so I’d need to have route for using a wireless adaptor. Most of my listening is blues and rock, no classical or opera. Most of my listening is in an environment that is noisy, though occasionally I will enjoy them in a peaceful quiet location. My questions: Is the technology of portable headphones changed at all in the past 5 years? Is there something new that they have done to make them better or higher quality? Has the technologies of the higher priced headphones filtered down to the mid-price ranges? Is there much data about build quality of particular brands or models? Based on my background above, What would be the current recommendations in the under $300 range? Thanks in advance!