It depends on some factors.
Clear QAM channels(or over the air if you have an antenna) will be picked up by the Digital part and if you still have analog, those will be picked up by the analog part.
Many places have or will soon be removing analog channels. This may require you to use a set top box. This is the part that makes things interesting because you need an IR blaster to control the BOX.
I also find many non hardware accelerated cards do not look as good on analog.
So in general for basic use, almost any USB tuner should work.