I bought a pair of these alleged MH1C's on Ebay after reading all the positive comments (hype?) on here. They have the Sony Ericson Logo on them so am I right in thinking they have sent the wrong ones?... however they still work fine on my Galaxy S player but I'm disapointed to say that I find them very thin, peaky and not loud enough, very underwhelming and not really that much better than the Samsung buds that came with the 'S'. They are probably as disapointing as when I first got my a pair of Re-Zero's Maybe the source doesn't suit them or maybe I just prefer a fuller, richer more bassy sound signature, I guess we all have different ears.
For those with similar tastes/ears as me, the Sony NC series earphones that came with the X, S and A? series players really are excellent... rich, deep, extended bass and have good clarity and can now be bought for only $16 plus postage.
Not 100% sure on compatability with other Daps all I know is that the ones that came with my X-series work fine with my 'S' and sound fantastic. See- http://www.lunashops.co.uk/goods-527.html