The Airport Extreme - Is it worth it?

I'm having some issue with my current D-link router with my iOS devices and I'm wondering if replacing it with an Airport Extreme might be a good move. In particular, I'm finding my iPad will occasionally drop it's WiFi connection and when I'm streaming something via Airplay it'll go silent for a few seconds every now and then.

I've got a multi-story house so I'm thinking going for something with a stronger Wifi range would be a good move - can anyone recommend anything here?