want to change bmw e46 gps navi,need your help

[fgrewf]

my boss want to set a gps navigation for my bmw e46 .let me collect some information for him.so i went for google search and fine a site .
Model: [OCG-6877]
Weight: [5Kg]
the price of the product: $588.00
what do u think about it ?
is it worthy to buy?
the site is BMW E46 M3 RADIO DVD GPS NAVIGATION COMMAND HEADUNIT BMW M3 Car GPS Navigation System DVD Player [OCG-6877] - $588.00 : Oemcargps - Oem Fit Aftermarket Car GPS Navigation Headunit for All Car Make Wholesale.
or if u knew some good sites
please tell m

[beemergal]

I thought you'd like to know, for Sat Nav disks, this is the place BMW Navigation Road map DVD 2012 update GPS sat nav systems as the guys here are friendly and helpful and I have no clue about this stuff lol great price too! The FULL 3DVD SET and V3.2 update disk all for £25

Instructon Manual and Navigation guides for all BMWs

[benben]

i bought the BMW E46 M3 navigation gps form the website, my friend recommend it to me, his one is nice , mine have just work for one week, nice so far, hope it can keep on,haha