Theyre good, i've got a couple. They have a power switch on the back, and appear to have improved louder sound output in comparison to some Dm500S clones. The V8 are the same ones that DealExtreme sell for 50 quid delivered...buy them form there instead if your not in a hurry.
Theyre not the same as a 518 though, The power supply is still external on these the 518 has internal power supply.