Looking at The MOTU UltraLite-mk3 Hybrid Audio Interface: Have read it does not like USB 3.0 ports and also that the Windows drivers are not real great? Looking at the Roalnd Octa, really my first choice: Read it definitely does not like USB 3.0 ports. It's for my laptop which of course only has 4 USB 3.0 ports. Killer laptop besides that. Yes, I do need that many ins and outs. At least 6 in and 6 or 8 out.
The issue with USB-3 is that on all motherboards except the newer Z series chipset units, the USB-3 ports are provided via 3rd-party add-on controllers. Liken this USB-3 scenario to using non-TI chipset Firewire controllers.
Many USB-2 audio interfaces don't cope well (or as well) as using the USB-2 controller that integrated into the motherboard's chipset.
With a laptop, you have limited USB ports... but with a desktop, you should have plenty of integrated USB-2 ports.
There's no performance advantage to using a USB-2 device connected to a USB-3 port.
I've been running USB-3 RAID units under Win7x64.
You don't need any special patch/drivers/updates/etc to get the full speed of USB-3.
USB-3 will top out in the ~500MB/Sec range (assuming you're connected to a USB-3 controller on a Z series chipset motherboard - integrated into the chipset).
The MOTU USB audio interface drivers are fine.
If you're using a Z series chipset motherboard (Z77, Z75), you'll likely do fine when connected via USB-3 ports.