Kong Mod - Slow router

I am new to this router flashing thing...I am trying to get a VPN connection set up on my router. Looked like this Kong mod was just what I needed.

However, I am having an issue with the speeds I am getting using the mod. 

Before the flash I would run a speed test (QOS is off on my router) and I was seeing ~300Mbps down and 30Mbps up.

I flashed to the default dd-wrt image and I saw the same speeds.

I then upgraded to the Kong mod and My download speeds caps out at just over 100Mbps. (The only thing I read was to disable so I did verify QoS is still disabled) 

Please help!