Wow, i don't know how i missed this the first time round.
Anyway, my experiences seem vastly different to the majority it would seem. When i started out recording i had a Maudio PCI thing (24/96 possibly) which, after much trying, discussion with people who seemed to know what they were doing, and cursing very loudly turned out just wouldn't play nice with my computer. I then moved on an Maudio USB Audiophile that very quickly became the bane of my existence due mainly due to driver issues. Even at uni the trusty Mbox's seemed to only work properly depending on their mood/time of day/ambient temperature/the tone of voice you used with them.
Then, due to where i was working, i moved over to Mac's 8 years ago, went firewire and never looked back. Second hand G4 Powerbook with Maudio Firewire Audiophile - fine and dandy. Upgraded to Macbook White with Audiophile - wonderful. Macbook white died after
a lot of....well.....hard use (and even then it was only the screen that went and i still used it for a year with an external monitor but it made portable recording difficult). When it came the time to replace the macbook white and upgrade my AI i very, VERY seriously considered a USB interface and a new macbook air. However, after 6 months or so of procrastination, general indecisiveness, and numerous roundabout discussions with friends and colleagues i ended up with a macbook pro and
the presonus firestudio mobile. Maybe it's not entirely future proof but i'm no rush to move back to the windows camp and firewire to thunderbolt adaptors are now readily available.
As i said, maybe it's just me, maybe i've just been lucky, but i'm in the "if it ain't broke, don't fix it" camp and seeing as i've had no trouble with firewire whereas i've experienced enough usb based hell for a lifetime i'm happy enough where i am