I don't use mac
I do use a firepod on a notebook

The main difference to me between the firepod and the firestudio is twofold:
1. firestudio has more inputs on adat (but you can daisy chain multiple firepods for more inputs)
2. firepod has no virtual mixer / routing / etc. and no direct outs

So if you regularly want to use different monitor/headphone mixes for several musicians at the same time, get the firestudio

But for the price of a firestudio you can get 2 firepods

Cheers

i don't know much about them, but i have heard that the firestudio is completely latency free. Im not possitive if the firepod is or not but i don't think it is.