So having ordered the Silverstone recommended by John, two days later the cheap no-name reader (that I've left plugged in and not working) starts to work without any intervention on my part. It continues to work.
The Silverstone has arrived and seems slightly better engineered than the cheap one, so I change them over and still everything is seen and working.
So, I try some tests:-
Copy a large 750mb file onto a fast CF card and also a USB3 memory stick.
Copying the files onto my Lenovo netbook with USB3 and I see about 120 mb/s reported in Windows explorer when copying the files. It's using a Fresco Logic controller.
Copying the same files from the same devices to the desktop and I only see 30 mb/s on both the VIA & Intel USB3 controllers, the same speed as the USB2 controllers on the system work at.
So it seems that both USB3 controllers aren't working at the proper speed.
Gigabyte finally got back with a new bios too, although it took three attempts for them to send an uncorrupted one to me. I've loaded that, but nothing has changed as far as I can discover.
Yes, all the drivers are up to date and loaded, no warning in device manager, just doesn't go as fast as it should.
Any ideas of what to try now ? Not much on the web about this that I can find yet.