Summary: I bought these because they were cheap. Yes, $60 is cheap in Korea for entry-level audiophile cans, due to horrendous import taxes. I chose the PX-100s after a good hour of A-B comparisons in-store with their rivals, principally models from Koss and Sony.
Pros: Light, portable, good sound quality for the price
Cons: Lack some sparkle at the top end, no isolation whatsoever
Summary: The PX100 is proof that something quite cheap and simple can provide as much enjoyment for the end user as something significantly more expensive. That's not to say that they're on the same level of quality as a higher end product, you do get what you pay for. It's a mental thing.
Pros: Pleasurable dark Signature, BASS, Comfort, Portability, Value, Replaceable padding, Built quality
Summary: I´ve owned these little bastards many years now, and loved every minute. They are compact in size, but huge in sound. And i mean hu-ge!
I remember when i bought these for travelling and to-go-field recording and just could not believe my ears.