I would highly recommend mi WiFi 3G instead of 3 even though it's Chinese firmware (app is in English/Google translate), I have used both, mainly due to much more powerful processor and gigabit ports and better stability.
Some comparisons that I have done
1)CPU usage is 8-9% while maxing out my 100 Mbps connection on 3G while it was 90-100% on 3.
2)I am able to access files on my HDD connected to USB 3.0 port on my router at around 950 Mbps through Ethernet connection on 3G compared to 100 Mbps on 3.
3)inbuilt torrent download manger gives around 6-7 MBps on 3G compared to 1-2MBps on 3.
4) overall better stability and better WiFi speed and range, double ram, gigabit ports, USB 3, powerful processor makes it future proof.