Indash DVD PLayer????

ok i have 2 questions. i have a indash dvd right now and i want to change it. i have an alpine cva 1003 hu ,so i might either go with an alpine if i can get a little extra cash but if not i was thinking the pioneer sdv-p7

--i saw that it can be used by itself or with a pioneer head unit. then some said that wasnt true.can anyone clarify this for me?

--alsoi seen a couple of dvd players with radios built in, i dont need the radio part but i liked its functions, so will that affect my system considering it has its own volume control , will it distor the sound from it??what do you think

please let me know

thanks

This is what they say about the use with a controller type system and stand alone:

If your using the CVA1003, it already have FM capabilities as well as XM radio, so you really don't need a DVD player with another FM receiver, this would be redundant and not necessary.