usb audio midi interface with preamps

$169.99 M-AUDIO Fast Track Pro Mobile USB Audio/MIDI Recording Interface with Preamps	$199.99 M-Audio Fast Track Pro 4/4 Mobile USB Audio/MIDI Interface with Preamps! #10534
$159.00 M-Audio Fast Track Pro 4 x 4 Mobile USB Midi Interface with Preamps	$219.99 AMERICAN AUDIO DV2 USB 2-Channel Preamp Midi DJ Mixer with i/o interface