I wasn't expecting much out of these because of mixed reviews.  I am not into new and technical stuff.  But I have a tv/dvd player that really needs help when it comes to the speakers.  I can hear fine, but spouse is losing some hearing.  Anyway I got this mainly for the portable tv/dvd player that I really like (RCA)- for the travel trailer.  So that's what I tried it with first.  COMPLETE AND AWESOME change to the sound.  Tried it on my ipod next.  AWESOME.  The sound is so much better and richer on both devices.  Tried it on a portable radio, OOPS, all static. with it plugged in , without- radio is fine...not designed for that older type radio I guess.I can't speak to the durability because I haven't had it long.  After I used it, I packaged it back up what it came in, instead of just the little carrying bag that comes with it.  The whole package is small, and adds extra protection.  But for us, it won't be used daily, etc.I think it's well worth the money I spent. 

Question: What about sound ?
Answer: COMPLETE AND AWESOME change to the sound