The RBH EP3 earphones are a no brainer in my opinion at their intro price of 99 bucks.
The HP2 is a pleasure of a headphone at a pretty incredible into price of $199 - hard to pass up.
The Oppo products follow the brands well designed, high end, refined feel perfectly but sometimes you want to loosen that tie
Do you like your music a bit sterile and technical like sound in a treated studio from professional musicians , the Oppos might be for you. Do you prefer live music in a downstairs club from great artists, the RBHs are probably for you.
The NAD really does achieve that "room feel" which is rare in a closed headphone. They sound great, but from the extra glossy finger print prone finish to the soft case and the ear cup on my ear, they did not get there for me. Still, very nice headphones and priced well