Arrow 3G with Sony PFR-V1 is nice.
Don't forget to install the foam sleeves on the bass ducts, to carefully (!!!) adjust their positioning into the ear canal and to set bass boost to "II". Still the result is on the lean side, like some faved nearfield monitors, but very acceptable.
I just received the Sonys and may add some further comments later on. I guess that there are ways to improve the bass by modding the foam sleeves. The system is open, i.e. not usable with other persons being present in the same room. On the other hand, the open design provides for a more open sound stage and eliminates "hot ears" which are common with conventional, circumaural headphones.
The PFR-V1 is a very weird looking set of ear speakers ("personal field speaker system" as per Sony lingo), discontinued by Sony and now available at a more acceptable price than the original, nothing less than hideously shocking $500 MSRP.