My experience with these headphones has been (comparing them to my Westone 4R's):
- Lighter on bass than the Westone's in a way I don't prefer (They have great bass compared to most headphones, but in my opinion not as good as the 4R's)
- They are very finicky in terms of placement and distortion. By this, if you don't place them with enough seal or at the right angle, music can get fuzzy at times (their website states this is because they need more isolation so they suggest moving them around). My 4R's never have this problem
- Their mids are more detailed than the 4R's in my experience. I can hear a more distinct seperation between instruments or sounds in the mid range than the 4R's - but not enough to warrant their lack of bass for my personal taste.
Love the microphone and buttons
I wish the 4R's had the UE 900's mids, but having to choose between the two I chose the 4R's