Will you just buy an interface already. All the ones in your price range are effectively the same with slightly different features. Just pick one that looks good.
Every couple weeks you post some other thread about firewire versus USB - SS drives versus traditional hard drives, etc. etc. Doing research is a good thing but it seems to me that you are taking it to such as extreme that you are never going to make a decision.
Are you trying to decide what interface to buy or are you just throwing up topics for discussion purely for curiosity?
If you are trying to decide on which one to buy, just post the ones you are deciding between and ask for opinions about them.
And they don't usually measure latency in increments smaller than a millisecond so 1 would be the fastest... It's a thousandth of a second - you get more latency being 10 feet away fron the speaker.
Thanks for noticing, this is motivating me.
"are you just throwing up topics for discussion purely for curiosity?"---> both
So, is the Fireface 400 and 800 the fastest.....i.e. lowest latency interfaces? I would prefer something a bit smaller in firewire. Like the apogee duet 1 firewire with more of the duet 2 specs. If RME had a firewire babyface, it would be bought and in transit to my house. I want a low latency, firewire, instrument in with a stereo line level pair in interface with a headphone and monitor out, all with volume/trim knobs, interface. Does this exist.
I looked at Motu Audio Express, TC electronics Impact twin, and the presonus firestudio mobile...................something about each gives me that feeling that maybe I didn't notice I was eating a hot dog that had veins in it. The Duets 2 and babyface are usb....I just don't want it.
I plan to buy 2 thunderbolt 7200 rpm external hard drives from lacie, so I want to run firewire for my interface. Usb will be for my mouse and an external usb flash drive to store my uploaded cd collection on.
Also, most usb interfaces are bus-powered and I just don't want power hi-jacked from my MBP. Say what you will, I just don't like it. Over time it just burns jacks up a lot faster and I preferred a self powered unit. Things like the duet 2 have apower supply, but then you are powering it up as well as forcing power back through the usb port.