No doubt the Mackie is a decent small mixer but you need to consider if you wish to invest in Firewire which, as a standard is rapidly being phased out. Because I do a lot of location work, I use a laptop and had a dickens of a time finding a machine I could adapt for Firewire (in my case using an Express Card slot. This situation will only get worse.
Also, consider whether there are enough mic pre amps (there's only three). The rest of your inputs will have to be at line level via the stereo inputs.
Frankly, you should likely evaluate the US1800. A lot of HR contributors (not including me) have them and speak highly of them. I'm sure somebody who knows the Tascam well will be along shortly.