Sonar 4 - what soundcard w/ preamps to get?

I've been looking around at a number of soundcards and also perusing a number of forums to decide on what soundcard to get. I know that the soundcard I need will definitely have to have WMD drivers for Sonar compatibilty. I would like the preamps for two mics for recording and possibly 4 inputs for simulatneous recording. Also would like to do firewire. I did visit the FAQ on this site for Pro-sumer cards such as M-audio, MOTU, Presonus Firepod/firebox, and still am lost. I thought thePresonus firepod or firebox. Some have sworn by the MOTUs. I wish I could spend thousands of $s but need to be a cost conscious. Someone had recommended Digidesign Mbox but I saw in the FAQ there were issues using with Sonar.

Any opinions would be appreciated. I guess I just want to be steered in the right direction.

Also, computer setup AMD Athelon, MAxtor 80GB SATA drives(RAID), ASUS board, 512MB RAM (with another 512 on the way).

Thanks for anyone's opinion on this.