well, first, I am a strong advocate of keeping the manufacture consistent among your various audio or video components, it almost always means the components wil integrate better, cross-control each other, etc.
But those Alpine DVD player prices are freakin' scarey
and I just so happen to have experience witha full-function DVD player that costs a ton less, and has performed well for me. (Of course, other products exist, this is just an endorsement from an acutal user). The DVD player I have is the Myron & Davis ADVD 270, it has a DIN size, it is a slot feed DVD player (meaning you have infinite flexibility with mounting locations, rather than just keeping it horizontal as with the tray feeder type) and it does all that the Alpine unit does - for about $350.
features:
DVD, VCD,SVCD,CD-R, CD-RW, MP3 Compatible
Slot Type Disc Feeder
On Screen Display Menu
Dolby Coaxial Digital Output Jack
Full Function Wireless Remote Control
Volume Control
Slow Play Back
4 Speed Scan
Zoom Feature
Step Play / Program Play
Frame By Frame / Slow Motion
A/V RCA Input For Video Games / Camcorders
Multiple Language Menu / Subtitles
Fast Forward / Reverse
18 Foot Wire Remote Sensor Eye
Multi Angle
NTSC/PAL Compatible
Mechanical/Four Seconds Memory Anti Shock
Dimensions: 7.0? X 2.0? X 6.8?
my .02 cents.