I want to upgrade my lights to Xenon in either brightest white or maybe blueish for my Crossfire, its completely black no silver trim anywhere

BUT I wasnt sure what was legal in regarding the Xenon lights....anyone have any idea .. I live in london but dont know where I can pick up lights that will pass an M.O.T , a lot of the conversion kits are illegal and will blind other drivers... anyone change there lights and have any knowledge? or know how good the blueish ones look? thanks