Summary: Upgraded from (a lot) of sony low/mid end earphones and headphones to SRH840, the sound was ok but the fit was aweful. Was looking for a small good quality earphones that was not very expensive. These fit the bill perfectly.
Pros: Fit. Excellent sound with Black filters directly from my iPhone.
Cons: Filters need to be replaced - not sure how often or how expensivce they are.
Summary: Do I like this IEM? Yeah.
Do I love them? Nope.
PFE is a single BA IEM, which possess, IMO, the stereotype signature of BAs in the market. The sound signature is about clarity, balanced, and non-fatiguing. While the headstage is quite narrow, the bass is anemic.