Looking to replace my NAD receiver. I can get the 4310 for $1800 or the 4311 for $2500 or the 7005 for $1800 or the 3008 for $2400. Im in canada so the prices are higher here, so anyways, is there a clear winner or something else I should look at? Cambridge audio? Should I stay with a Nad? My speakers are 600 ser. B and W's. Please help, any comments or suggestions welcome.:)