With difficulty, seeing as the Netgem is for DTT ie freeview through an aerial, and the ntl are for cable.
I have a Daewoo freeview thing, and the Netgem I've also seen- it's pretty good, you can get wireless keyboards and stuff and surf the net on your TV... I think it may even be as good in terms of tuner sensitivity, the SetPal tuner has been slutted around quite a bit.

BTW