Upgrading speakers in a Mercedes ML

[JonWill]

I have a 2001 Mercedes ML320 which had the base stereo installed (Audio 10 radio/ cassette and 4 speakers). I assume it's the same system on most Mercs of the same vintage... I have upgraded the head unit to a Kenwood KDC-BT61U, and am still dissappointed with the sound. I'm keen to upgrade the speakers, and there are a few ways to go:

• Drop in new speakers into the existing holes - any suggestions/ how easy is it to get to them?
• Add a subwoofer - my head unit has an out for a sub, but wiring will obviously be tricky
• Add new front speakers/ and seperate tweeters into the front - is it easy to find space in the door panel/ get it off?
• Do both of the last 2

Does anyone have any suggestions as to speakers I copuld use? Looking for a project over Xmas on a tight budget - may scour ebay for speakers!

Thanks for any help!

Jon

 

[JonWill]

Someone has recommended these to me:
Edge Audio ed306 http://www.halfords.com/webapp/wcs/..._productId_723485_langId_-1_categoryId_165707
Never heard of Edge - any positive throughts? Or should I stick with Kenwood/ Alpine or Clarion?