I have been using an atheros based mini pci card in my laptops with BT4 and its worked pretty well. However, I want to add a VERY directional antenna to my setup so I need something with an sma plug, etc. In looking around at the sea of adaptors, I was wondering if anyone knows one that fits ALL of the following:

1) Known to work perfectly well with BT4
2) USB interface
3) External antenna connector (sma is probably preferred)
4) Can do G and N

Thanks!