Normally I'd not particularly recommend a Mac but since they have Firewire built in it's easier. When I had to use Firewire I had no issue with a random Firewire card off eBay, whereas my friend had to go through 3 before he found one that worked and even then it's a bit flaky. I will say that generally, if you looked for a used gaming PC around $300 you'd get better performance than an equivalent price point used Mac, then you'd just have to put a firewire card in there.