There are dozens on the market. Budget and input count required will probably narrow it down quickly. MOTU seems to have a strong following with mac users. Metric Halo is generally considered top of the line. Focusrite and Presonus are middle of the road. Maudio is more budget minded.
One thing to keep in mind... there are "bus powered" ones and ones which require external power. The bus powered ones get their power from the USB or firewire on your computer. Seems handy, but it puts a lot of constraints on the electronics designer who only has so much power to draw from. So maybe they have to cut corners, and maybe they don't have as much headroom as external powered ones.
When it comes to preamps... a lot of people around here who use Grace, Apogee, and Portico for a 2 or 4 track rig may scoff at using lesser gear for multitrack. While most of us can't afford high end x 24 channels, there is also a reality check... I can justify having a good preamp behind Schoeps, but do I need a highend preamp behind an SM57 on a distorted guitar cab, etc? I don't think so. The concept of "this is good enough" comes into play for me.