Arduino Mega + XBee-PRO® 868 OEM RF Modules

Hi there!!

I'm a student from Brazil, and i've some questions about Xbee-Pro 868. If anyone could help me, i appreciate!
I'm making a Kart cross by remoto control! Arduino will control 5 engines (with potentiometer) and things like speed and tachometer. But i don't know if the Xbee really reaches this distance (40km for RSPMA) and if here can send and receive all this informations making the kart work well. Anyone have already use it, and can give me the answers?

The Xbee link: http://www.digi.com/products/wireless/point-multipoint/xbee-pro-868.jsp

Sorry for the wrong english.
Thanks!
Renke