And, Welcome to my World.
I officially got my first pair of ER4S today. These mark my first time listening to ER4, after a long love affair with the HF5 and related models. I'm really shocked how big of a difference there is in quality between the HF5 and ER4. The higher price for the ER4 is totally warranted if you feel the HF5 is properly priced at around $100. Amazing quality.