Printer Help

[Maxwell]

I need a good printer that will handle medium-ish volume. Yet I have no idea how to search for it. Here's what I need:

• 8.5" x 11" paper input (that's all I really need)
• Black/White only (color not needed)
• Dual sided printing (KEY ELEMENT)
• FAST dual-sided printing (must be automatic)
• Able to handle a moderate volume

The cheaper the better, all else equal, but I have to have the features I just outlined. I'd rather spend (school money) $400 on a printer that does the above fast than $200 that does the above slowly...

Any advice would be appreciated.

EDIT:
I found three, but have no idea if they'll print dual-sided quickly. If you have experience/knowledge, I'd love to hear it...
http://www.newegg.com/Product/Produc...82E16828115365
http://www.newegg.com/Product/Produc...82E16828106511
http://www.newegg.com/Product/Produc...82E16828106505