A half gram of proper crystal MDMA and you'll chip teeth! I take bombs varying in size from about 100 - 300mg in one dose. Anymore is risking an overdose or at least a very unpleasant comedown... Wouldn't advise it.
Two of those white hearts around most of the U.K is a perfect dose though. Around 160-180mg. They're actually better than some MDMA i've had. They're made in Holland so its likely to be better MDMA.. Theres also very little filler in them, one of the cleanest pills around!:D