I'm also looking for a system with wireless speakers, I have narrowed it down to two (I think!!), The Sony Dav-DZ700F and the LG LHW-551TB, I have not heard either system yet so if anyone out there owns either one feedback would be appreciated.
Keep us updated to which system you go for Nickj24.
I purchased an LG LH-W751TA1 - it's like the 551 but with a bit more power and an optical in socket. It was around £330.
Only the rear speakers are wireless, which makes sense really. One of the rear speakers is the wireless receiver and it connects via speaker cable to the other rear speaker. The rear speaker that is the receiver needs to be plugged in to the mains for power.
The speakers work really well. The only grumble I have with the system is that the receiver fan cuts in at volume 11 and is quite noisy.