coffeebaron: Unfortunately you need K band, as that's what the mobile cameras are on. We use to be lucky in NZ for a while with only KA band, but then came Redflex :(
I use the R7, you can get up to 500m speed cam detection if you mount the detector vertically. There is a NZ guy on rdforum.org who writes a custom firmware for the international R7.
Do you get a lot of flase alearts with K enabled? or can you set the freq with the R7