As far as a sound quality to ease of use to EXTREMELY low price ratio is concerned... I think you would be a fool to NOT think hard and long about the new MOTU 828mkII.
It is Firewire (i.e. no bumbling PCI card to install, configure, de-install, find the IRQ interupt, re-install, swear a lot, start haging your computer, and then finally call a friend). It has 10 inputs and outputs. It can be daisy chained a couple of times, so you could have 10, 20, 30 and I think even 40 inputs and outputs.
It has two killer pre-amps (for that price) per unit. it has digital I/O.
It is basically the 2408mkIII without the messy card business, and I do believe it doesn't have the TDIF. (but who uses that anyway unless you are running a big front end mixer or something?) And it is a couple hundred dollars cheaper than the 2408mkIII.
I think it basically depends on what your needs are. If you have a lot of digital thing-a-mah-jiggies i.e. drum machines, synths, samplers, sequencers etc. Then digital I/O might be more of a priority. But if you are just recording yourself with a guitar and want to overdub parts, or you are in a full band and want to multi-track record the next top 100 rock song, then I would say that analog I/O is higher on the priority list. i.e. GET A MOTU 828mkII.
And if your drummer has a double kick drum and 300 drums and cymbals and you record live with a 20 pice choir... get a MOTU 24i. It has the PCI-424 card to install, but it does have 24 analog ins and outs in one unit. The last of the great PCI card units (I hope!)
I HATE cards!