Want buy a wireless 802.11n USB adapter

Hello everybody,
I'd like to purchase a 802.11n USB adapter (I have a compatible router) for my PC.

These are the ones I'm currently looking at:
Edimax's EW-7622UMn

Edimax's EW-7612UAn

D-Link's DWA-140

Any suggestions which one I should take? Maybe there's something better than these three?

Also, if these USB adapters are much slower than say an Edimax EW-7722IN PCI card, should I take this PCI card instead (or maybe a better one at the same price range) ?

The best USB adapter is the engenius 600mW EUB9603H

Keenan Systems Wireless Store Featuring Engenius

It is super long range and suports 802.11n it also has a virtual AP mode to share wifi wil lower powered devices aroudn your PC like a Iphone.

You get what you pay for with WiFi adapter the cheaper ones use low quality chipsets with low transmit power and range.

MERU AP300 SERIES ACCESS POINT 802.11n

i hear the engeinus and alfa brand names are one of the best.