I have audiobahn 4inch splits 80watts rms wild sound man. $220-00 though but worth it. They just fit into the stock location and I put the tweeters on the dash at the corner of the window.

If you want to kee the car looking clean and neat just replace the speakers in the dash, the 100watt Avalanche 4" i've got in my VL go better then my cousins 4" 120watt xplods, could just be the setup though

I got a set of pioneer 4 inch splits in the factory position. woofer in the stock spot, tweeter sitting on the grill... looks really good. Also, Iv got a pair of Clarion srs1325 splits which I got on special for $110 in my doors with only an MDF spacer. These are the same speakers you're talking about murdercity only a bit smaller (13cm) and yes they are good, tho they lack bass. Soon these will be moved to the parcel shelf and replaced with srs1751hx ($450 odd)