Do all USB mixers suffer from latency? How about firewire?
 

Just bought one. It's cheap, but seems that it might be a standard trait.

Latency
 

YES. they all suffer from it in some sort or fashion. the time that it takes to do the Analog to digital conversion on top of Digital to analog conversion. some have crafty ways to make it sound like there is none there but in reality its always there. Some let you monitor your input before it gets converted and mutes the recording track, then it aligns it to the session. and if the system is a nice high end unit the latency may just not be noticeable.

This is a big subject.

You need to use ASIO sound/drivers. With a fast computer the latency will be imperceptibly lower.

Some sound cards/software allow 0 latency monitoring while recording.