After 6 months of testing:
+
The helmet is still in very good condition, it is the quality despite the presence of plastic mass
The sound is excellent: rich bass and treble well balanced (no need to tweak the equalizer for me)
The size is reduced when folded: 2 earpieces swivel and fold to the inside of the headband
Listening to a single ear, rotate a headset
The flat wire avoids knots
Jack angled: lifetime ++ cable (to assess over time)
-
Perfectible sound insulation: you hear outside noises and people around you hear music
Not super comfortable after a while
Plastic creaking noises
The first 2 statements are negative aspects specific to supra aural headphones. If I wanted to avoid these drawbacks I'd turned to a circum aural headphones.
I recommend this helmet for those looking for a portable headset, light, robust with good sound quality.
If you want comfort and sound insulation, turn to circum aural headphones (which includes the ear)