I totally agree. I just finished switching out my Intel Centrino 6235 Advanced N out for one of these:
http://www.sparklan.com/product.php?func=view&prod_id=215
It's a bit more pricey than most of the other alternatives, but I wanted something reputable that wasn't thrown together by some OEM looking to cut costs down to the bone or something ripped out of some other machine.
Note: When you compile the list, you'll probably want to distinguish between adapters that [a] support dual band and [b] have Bluetooth capabilities. Both dual band and bluetooth are requirements for me and the combination of these two features severely limited the list of possible replacements. One of the great things about the Centrino was that it was cheap and that it had these features. Sadly the software for the card just doesn't some capable of keeping up with the hardware.