I am looking at a Zoom PS-04 and a Fostex MR-8 Mk II.
Which one do you guys recommend? I am looking to record guitar, bass, drums, vocals. It is meant to be a demo, and we play a punk style of music.
If you guys don't recommended either of them, what multi track recorder do you recommend?
Definitely go with the Fostex out of those two options. With the Zoom, you'll very quickly find yourself running out of tracks. No matter how much you think you'll only need guitar, bass, drums and vocals, you'll very quickly find yourself wanting to add an extra guitar part here & there.

I can also recommend Fostex as a good choice - I had one (the VF80, a predecessor of the one you're considering) for several years and it served me well.

It's also worth looking on the used market for multitrackers though, for the price of a brand new 8 track you can often get a used 16 track that is still in perfect condition.
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