Pioneer Dvd head units queries.

[Zoomsixfred]

Hi bros, I'm must say I'm pretty new in ICE and i really need help in some stuff. Well, I'm currently shopping around for DVD players in the car and due to budget constrains, I've been looking for second hand head units. I've been quoted $1500 for the following: A second hand Pioneer AVX-7000 together with AVM p9000r(i assume?) and a XDV-p90 DVD changer. I think it also includes an analogue tv tuner but i don't know the details of it. Can you guys please advise? I'm also looking at first hand JVC KD-AVX1 and Pioneer DVH P-5850MP then intend to add a monitor to it or something. Any guys have any experiences with the sound quality of them? Please advice. Pardon the long thread. Hee...