It's only 10/100 Ethernet, I can't see it being limited too much by the Bus speed. I've tested an apple-branded USB 10/100 Ethernet adapter at ~98Mbit on a beaglebone.
Right. USB 2.0 is already packetized with a MTU larger than ethernet already. The net overhead for the USB stack is near zero. It's true that fancy ethernet devices can do things like TCP or encryption offload, scatter-gather DMA for zero-copy transfers, etc... And clearly this isn't going to do that stuff. But if all you want is to get packets on and off the wire, there's nothing wrond with USB 2.0 Hi-Speed.
(FWIW: that apple-branded adapter is almost certainly an ASIX part -- the same chipset is sold under dozens of brands and works quite well in my experience.)
This one caught my eye. I'm not sure if the i.MX 6 quad is as capable as the exynos and there's only 1GB of RAM, but the board has SATA (there's a controller built into the SoC AFAICT) and Gigabit ethernet on an RGMII interface. Not that I really know what that means, other than I'm guessing a dedicated, gigabit-capable interface on the SoC. There's also PCIe which they're apparently going to release a breakout daughter-board for at some point.
Of course this board is not all that cheap compared to the ODROID.
I received mine about a month after I backed the indiegogo campaign. They shipped mine using DHL and it arrived before they sent me the tracking number.
Shouldn't be a big deal so long as it's got a decent USB controller. The reason the Raspberry Pi has so many issues with USB and excessive CPU usage is that the onboard USB controller is really dumb and mostly implemented in software.
Something like this with SATA and Ethernet on a fast bus would be awesome