Summary: I'd like to think RHA for sending me these earphones for review.
Along with the summary below, I have posted a Youtube video review of the MA450i. If you like the video, check out my channel for more reviews :)
The MA450i has an interesting build, with a reverse horn / funnel shape. This is actually the opposite of a horn speaker design in principle, and means that the MA350 fits very comfortably in the ear.
Pros: Durable metal earpieces, comfortable fit, deep bass, good included accessories
Cons: Tangly cables, lacks a little clarity, driver flex