No you are not
If you are going to connect an SSD I strongly suggest you use a USB3 to SATA bridge.
Also please note that the UP board comes with a USB3 OTG port (micro USB3).
I've bench marked my SSD over USB3.Benchmark results
Its running of a hub mind with lots of other things attached!
I have an OTG USB 3.0 and have attached a plugable USB 3.0 docking station to give me 2 USB 3.0 and 2 USB 2.0 ports, gigabit ethernet, 2 more displays and audio in out.
Works a charm and has been working for 2 months now without a hitch! Even added a blutooth 4 device so i can play music from android devices through my up board.
I have a USB 3.0 2TB HDD attached for backups (cwRsync for windows) and user storage + apps.
Wrote this on my Up board win 10 from my workshop.