Just got the RT-N66U model today. I am not sure why but setting up Unifi wasn't smooth. I couldn't get it to work during the turning the modem off/on procedure, and only when I tried the setup many times it finally worked.

Also, maybe I am asking too much, but the WIFI signal has only gained one bar (2 bars to 3)and gained 20% (45% to 65%) on my PS3 compared to the stock Unifi router. Can I do anything extra to further improve the signal?

Yeah, I have the latest firmware.

The one bar is for my phone and tablet signal.

I'm using a LG Nexus 4. But I don't think it's the phone, I get full bars near the router. It's just my house has many layers of brickwalls which weakens the signal and I was hoping this router will increase it. I was hoping for full bars for the whole house, but maybe that's asking too much.

Anyway, I tried moving the antennas so they all face my PS3 and it's now at 80% and so I'm quite satisfied now.