I am going to install a Kenwood or JVC with all in one (mp3-dvd-lcd,similiar to the pioneer avic) to replace the business cd radio,like one of these:

JVC KW-AVX706
Jvc KD-AV7001
kenwood KVT-627DVD


Is it possible to keep the steering wheel control,with these radio?
Is it also possible(but I suppose not) to leave the radio on for controlling only the computer,without damage the electronic system of the car ?

I use the TomTom on PDA(that I use for work)with the gps bluetooth,so I can't sell it.

Thanx,Marco