Best value for money on the market

I purchased a DVN39 for my 99 E39. While the car is in great condition, the sound system had all the usual failings and no G
PS. After installing the unit, I couldn't get the GPS to work. The vendors of this product are support champions and eventually replaced this unit with a new one. With everything now up and running, this unit looks and feels like an OEM unit. It has so many options and features that I challenge anybody to show good reason why a feature has been missed for an E39 installation. The GPS is accurate and packed with features yet very simple to use.
The radio has everything including traffic alerts. The stereo is well featured, but has average sound and is probably only as good as the original E39 speakers in my car. Having said that, the DVN unit has more than enough outputs on the back to drive an off board, monster system of your choice including a separate subwoofer. For about 300 GBP, I doubt that you are going to find an E39 drop in replacement unit, that has as many well developed and useful features. On top of all that, the unit integrates beautifully with the existing E39 decor.