Airport Extreme and multiple HDD's

Okej guys i have an question for you …

i see here that a lot of you have an airport extreme with multiple hdd’s connected to there atv2 … 

What kinda USB Hubs (brand, model) do you guys use? I wanne buy one, but don’t know whats a good one to use.

Thanks for you help!

I have been having problems with mine.  I have tried several and I think it comes down to that I need a hub that has a power supply.

I finally bought a Sitecom usb hub … … Works perfect!