Using XBee Radio Modules in dense urban areas

I am looking to use the XBee for wireless communication between art projects at a large music festival. I just need to send the values of a few faders and buttons. I have notoriously had trouble using my iPad to connect with my Mac over an "ad-hoc network" just a few feet away because of the extremely dense networks and communications taking place - both wifi and cellular (think 30,000 people using their cellphones all day).

I want to know if this product may be vulnerable to the same woes? I read the XBee usually uses a 2.4Ghz frequency (which is the same my ad-hoc wifi used) so I am worried it will be troubled just the same.

I only need to transmit 1 city block. So it sounds like I may need the pro version. I just need to know if it will suffer interference.

Thanks for any insight! I am open to other ideas for transmission if this looks like it won't work.

Every device in this band is roughly using the same frequency, like cellphones use the same frequency to communicate. Nevertheless, they don't interfere!
They use spread-spectrum technics to avoid interference. Those technics allow multiple devices to operate at the same carrier frequency at the same time.

So don't worry, you can use your XBee there.