it is around 2000 max which is why there is 2,000 IPTV Channels in the list by our respected member @ FENEKI
i know for sure it takes up many,many hours for him to compile his iptv lists and it is appreciated .
TM5402 M3 HD offers a lot fast blind scan and recording feature with Youtube , im sure you'll be very happy with it
and plze do post back here if you have any issues or questions that we can help you with : ))
Good luck !