I use 2 units
1 the Wifi card from Linksys PCI Card and one of their USB
Both are at least 45 feet away from the access point and pass through 4 walls
The USB works best and it includes a 6 foot USB cable to allow you to place it where you want it for best reception
I place it above the system on a shelf and have good speed.
Can't give you any examples because I never needed any or even ran a speed test on it
it works and I can tolerate it ( I HATE SLOW CONNECTION )
But the Linksys units work with NO hassles