T.V. TUNER

Hi all, can anyone recomend a tv tuner, i have a kenwood dnx 5220 media system fitted and would like to add a dvb tuner to it,the kenwood one seems very expensive so i just wonderd if anyone is using a different one and what your opinion is,also i need to look at aireals as since changing the original system my radio is awful,may have to put an external one on ot or are there any decent internal ones out there, ideally it would be a sharks fin that did fm,am gps and tv but i don't think there is such a thing out there.
Thanks in advance,
Matt