I have both Aria and HM. They have different characteristics. But HM has great advantage with its price and included accessories.
HM stands out for its clear, bright presentation. It has lighter bass with a sweet sub bass extension. If you want it to slam harder, it responds to EQ very well.
Mids are great especially female vocals. Hzsound wrote the reason really nicely why they name it this way.
And I really agree with this description. Such pure, clear, bright sounding iem with great technicalities for its price range. Vocals sound really transparent. The timbre is really good and soundstage is very deep. I managed to get better scene by changing the cable to a pure copper cable. This also lead me to take its brightness. It's really good with instrumental songs, Jazz, Ambient, Chillout etc. But I don't think it's suitable for Rock, Pop, R&B etc. Because of being bass light.
On the other hand, we have Aria with a tonality that everyone would like and that could fit almost anything, at least would handle more than HM.
Aria stands out for its beautifully rumbling bass. Really deep, slams hard and quite agile.
Mids are slightly recessed and sometimes thin sounding but I really don't mind laid back presentation as I use it for listening to different kinds of music.
Treble is really great with a decent amount air and extension in the ultra high end.
Timbre is really good as well with a decent soundstage. Imaging can be improved by taking out the filter hexagonal holes leaving the other black taped one.
Aria's stock cable doesn't reflect its potential and matching aria with a pure silver cable improves its technicalities adding more edge.
Long story short, if you like bright sounding iem, go for HM. If you doesn't wanna spend much go for HM and try to EQ it to your taste. If you want to cover most of your library (assuming that you listen to many different types of songs like me) go for Aria. I can't tell that Aria deserves the price difference but buying Aria is a secure way because of its characteristics.
