The recent success of HiFiMAN is definitely deserved. Not only are they pushing the upper limits for the level of sound quality achievable with a set of headphones, they are also largely responsible for the revival of the old yet obviously interesting planar magnetic technology. The HE-500s are a real feat of engineering. When we first heard the enormously power hungry HE-6s we did not believe that a quite efficient version could be made to sound almost the same.

The HE-500s are very close to the HE-6s and for $300 less and the ability to drive them to their potential without dishing out over $1000 worth of amplifiers makes them brilliant value. They are easier to power than the HE-6 main rival, the Sennheiser HD-800s and exhibit a sound signature that will please the majority of people out there. The spectacular part about that is that music still retains an absurd amount of details throughout the frequency range.
Nothing is ever good enough in the world of Hi-Fi but the HE-500s provide you with an über high-end experience for just $899. A decent setup with a iPod line-out into a $300 stationary amplifier will give most listeners a real surprise.
On the down side for $899 you would expect a better cable and more comfortable ear pads. The ear pads are being reworked right now, but no word yet on the cable.