I reset my router and EX4 to the factory defaults at the same time. The router was back online before the EX4 - I don’t know if that made a difference. After that, I had reasonable data transfer speeds.
I had to set my home WiFi back up but that was not a big deal.
I was also experiencing connectivity issues. The EX4 would suddenly become unavailable sometimes in the middle of large data transfers. So I went to my network adapter in Device Manager (Windows 8) and to Power Management once I selected the adaptor and I turned off the feature that lets the adapter sleep to save power.
For Windows 8 - Device Manager > Network adapters > (select your adapter - it should be easy to spot) > Right Click on it > Properties > Power Management > Then uncheck "Allow the computer to turn off this device to save power.
This is critical for wireless connections because your adapter will shut down, but this is also helpful for wired connections.
Last note - I have not yet set a static IP for my EX4 and I still get fairly decent performance from it. I will do a static IP later but I spent a lot of time looking at that issue previously as it is widely mentioned online and yet it turned out to be a distraction from the real problem I was having.