What audio interfaces can I use with Sonic Studio applications?

"All Core Audio–compliant interfaces for external audio I/O are nominally supported. Unlike FireWire however, USB does not provide an isochronous or time–critical data delivery mode. So, USB–attached products for external audio I/O are not recommended for either optical disc or audio interfaces when used in any pro audio production environment. USB peripherals, other than HUI products such as mice and keyboards, may interfere with the operation of our products."

Hi all
After reading the above recommendations I started doubting about the best way to connect my rme ucx and my mac mini.
They are currently in usb3 mode but as said after reading the above statement I started wondering if would be better a firewire 800 to 400 cable.
I currently use soundblade se.

http://www.sonicstudio.com/sonic/support/i-o.html

Thanks in advance
Alessandro