you WANT the HD radio! Trust me.
When I was looking, I decided that I wanted the HD radio and NAV and preferred to stick with the 17" wheels (due to cost). I think the only one the dealer had with those specs was in a color my wife didn't like.
I decided I could do without the nice radio because there are very few HD radio stations in my area, so it wouldn't get used much anyway. Plus, if I end up activating the navigation in my car, I'd probably eventually decide to pay up for map updates, so I guess I save even a little more with the cheaper 8.4" infotainment option.
I think all cars should come with HD radios these days just because it is awesome, but I was very disappointed 2 years ago when I moved and plugged in my HD radio in my house, scanned for channels and it only found a couple of them

. Plus, on road trips, the XM radio is much more useful than HD because you can listen to stations across a much larger area (though scanning through FM or AM can be fun sometimes too, but not when there is nothing there!). Later, I'll have to decide if I want to activate my Nav ready unit, or if I want to continue the XM once the free trial expires (would SiriusXM even still exist if it wasn't for the deals they have with car makers?).