I picked it up at bestbuy only because it was local, good places are always frys.com and newegg.com if in stock. Setting up is a piece of cake. Complete plug and play.
It does comes with a cd which basically sets up a network drive when you plug in a HDD or USB key, you could do it on your own if you're familiar with the process.
My setup is linksys N Pci card in my media center desktop, xbox 360 with wireless adapter, and old laptop with BG wifi (i do have a wusb600n but have not set that up yet)
router groups BGN on 2.4 and AN on 5ghz
360 - before router i had to use ethernet since wifi lagged, after router i can use the adapter on the .11A 5ghz frequency... rock solid
Desktop - no difference really before or after but overall more speed on transfers and Netflix barely ever stutters.
Laptop - Same
The interface is easy to understand and setup for anyone and it also has many options to configure, if tweaking is your thing.
Using it for a week now and i dont see any downsides... and from what i've read, neither does any1 really. g'luck