Have to know the chipset used and protocol. From a quick look at their site I'd guess they are just using rebrands of other brands (quads look quite generic), so wouldn't be suprised if they used an NRF24l compatible chip and one of the available protocols.
One of the troubles is figuring out what it really is, ie. a known manufacturer. Otherwise try to take photos of the transmitter's circuit board, with clear images of any printing on any main chips, and then doing a packet sniff; not for your average user (I still haven't done one, even though I have the tools... somewhere in the garage... maybe...)
