The kickass Ultimate Ears 18+ Pro headphone will fit your ears perfectlySteve Guttenberg of c|net says:
If you're craving the ultimate sound, the UE 18+ Pro is the headphone to check out.
Steve also said that "Ultimate Ears' Reference Remastered was one of my favorite in-ear headphones of 2016, so I was more than ready to take on UE's refreshed flagship, the UE 18+ Pro." and that "each UE 18+ Pro earpiece houses six proprietary balanced armature drivers that are divided into four frequency bands. Its impedance is rated at 37.5 ohms, making the UE 18+ Pro easy to drive. It'll sound dandy plugged into your phone."
Read the rest of Steve's review for the best in-ear monitor available.